2014-02-26 19:11:54 +01:00
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/*****************************************************************************
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2017-05-15 17:17:16 +03:00
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Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
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2014-02-26 19:11:54 +01:00
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Copyright (c) 2009, Percona Inc.
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MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
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Copyright (c) 2013, 2023, MariaDB Corporation.
|
2014-02-26 19:11:54 +01:00
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Portions of this file contain modifications contributed and copyrighted
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by Percona Inc.. Those modifications are
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gratefully acknowledged and are described briefly in the InnoDB
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documentation. The contributions by Percona Inc. are incorporated with
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their permission, and subject to the conditions contained in the file
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COPYING.Percona.
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
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Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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You should have received a copy of the GNU General Public License along with
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this program; if not, write to the Free Software Foundation, Inc.,
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2019-05-11 19:25:02 +03:00
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51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
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2014-02-26 19:11:54 +01:00
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*****************************************************************************/
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/********************************************************************//**
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@file srv/srv0start.cc
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Starts the InnoDB database server
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Created 2/16/1996 Heikki Tuuri
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*************************************************************************/
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2016-08-12 11:17:45 +03:00
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#include "my_global.h"
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2014-02-26 19:23:04 +01:00
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#include "mysqld.h"
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2016-08-12 11:17:45 +03:00
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#include "mysql/psi/mysql_stage.h"
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#include "mysql/psi/psi.h"
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|
2014-02-26 19:23:04 +01:00
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|
#include "row0ftsort.h"
|
2014-02-26 19:11:54 +01:00
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#include "ut0mem.h"
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#include "mem0mem.h"
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#include "data0data.h"
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|
#include "data0type.h"
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|
|
#include "dict0dict.h"
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|
#include "buf0buf.h"
|
2020-01-21 15:46:20 +02:00
|
|
|
#include "buf0dblwr.h"
|
2014-02-26 19:11:54 +01:00
|
|
|
#include "buf0dump.h"
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#include "os0file.h"
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#include "fil0fil.h"
|
2015-04-01 11:50:21 +03:00
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|
|
#include "fil0crypt.h"
|
2014-02-26 19:11:54 +01:00
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|
|
#include "fsp0fsp.h"
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|
#include "rem0rec.h"
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|
|
#include "mtr0mtr.h"
|
2017-02-10 12:11:42 +02:00
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|
|
#include "log0crypt.h"
|
2014-02-26 19:11:54 +01:00
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|
#include "log0recv.h"
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#include "page0page.h"
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#include "page0cur.h"
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#include "trx0trx.h"
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|
#include "trx0sys.h"
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#include "btr0btr.h"
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#include "btr0cur.h"
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#include "rem0rec.h"
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#include "srv0start.h"
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|
|
#include "srv0srv.h"
|
2014-08-06 15:28:58 +03:00
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|
|
#include "btr0defragment.h"
|
2017-08-31 08:27:59 +03:00
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|
|
#include "mysql/service_wsrep.h" /* wsrep_recovery */
|
2016-12-30 15:04:10 +02:00
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|
|
#include "trx0rseg.h"
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|
|
|
#include "buf0flu.h"
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|
|
|
#include "buf0rea.h"
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|
|
|
#include "dict0boot.h"
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|
|
|
#include "dict0load.h"
|
|
|
|
#include "dict0stats_bg.h"
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|
|
|
#include "que0que.h"
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|
|
|
#include "lock0lock.h"
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|
|
|
#include "trx0roll.h"
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|
|
|
#include "trx0purge.h"
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|
|
|
#include "lock0lock.h"
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|
|
|
#include "pars0pars.h"
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|
|
|
#include "btr0sea.h"
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|
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|
#include "rem0cmp.h"
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|
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|
#include "dict0crea.h"
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|
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#include "row0ins.h"
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|
|
|
#include "row0sel.h"
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|
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|
#include "row0upd.h"
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#include "row0row.h"
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#include "row0mysql.h"
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|
|
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#include "btr0pcur.h"
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
#include "ibuf0ibuf.h"
|
2016-12-30 15:04:10 +02:00
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|
|
#include "zlib.h"
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
#include "log.h"
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2020-08-04 06:59:29 +03:00
|
|
|
/** We are prepared for a situation that we have this many threads waiting for
|
2020-12-04 18:07:25 +02:00
|
|
|
a transactional lock inside InnoDB. srv_start() sets the value. */
|
2020-08-04 06:59:29 +03:00
|
|
|
ulint srv_max_n_threads;
|
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
/** Log sequence number at shutdown */
|
2016-08-12 11:17:45 +03:00
|
|
|
lsn_t srv_shutdown_lsn;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
/** TRUE if a raw partition is in use */
|
2017-04-25 09:26:01 +03:00
|
|
|
ibool srv_start_raw_disk_in_use;
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2017-05-15 17:17:16 +03:00
|
|
|
/** UNDO tablespaces starts with space id. */
|
2021-07-22 11:22:47 +03:00
|
|
|
uint32_t srv_undo_space_id_start;
|
2017-05-15 17:17:16 +03:00
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
/** TRUE if the server is being started, before rolling back any
|
|
|
|
incomplete transactions */
|
2017-04-25 09:26:01 +03:00
|
|
|
bool srv_startup_is_before_trx_rollback_phase;
|
2014-02-26 19:11:54 +01:00
|
|
|
/** TRUE if the server is being started */
|
2017-04-25 09:26:01 +03:00
|
|
|
bool srv_is_being_started;
|
2014-02-26 19:11:54 +01:00
|
|
|
/** TRUE if the server was successfully started */
|
2017-04-25 09:26:01 +03:00
|
|
|
bool srv_was_started;
|
2018-04-29 09:41:42 +03:00
|
|
|
/** whether srv_start() has been called */
|
2017-06-12 17:43:07 +03:00
|
|
|
static bool srv_start_has_been_called;
|
MDEV-13039 innodb_fast_shutdown=0 may fail to purge all undo log
When a slow shutdown is performed soon after spawning some work for
background threads that can create or commit transactions, it is possible
that new transactions are started or committed after the purge has finished.
This is violating the specification of innodb_fast_shutdown=0, namely that
the purge must be completed. (None of the history of the recent transactions
would be purged.)
Also, it is possible that the purge threads would exit in slow shutdown
while there exist active transactions, such as recovered incomplete
transactions that are being rolled back. Thus, the slow shutdown could
fail to purge some undo log that becomes purgeable after the transaction
commit or rollback.
srv_undo_sources: A flag that indicates if undo log can be generated
or the persistent, whether by background threads or by user SQL.
Even when this flag is clear, active transactions that already exist
in the system may be committed or rolled back.
innodb_shutdown(): Renamed from innobase_shutdown_for_mysql().
Do not return an error code; the operation never fails.
Clear the srv_undo_sources flag, and also ensure that the background
DROP TABLE queue is empty.
srv_purge_should_exit(): Do not allow the purge to exit if
srv_undo_sources are active or the background DROP TABLE queue is not
empty, or in slow shutdown, if any active transactions exist
(and are being rolled back).
srv_purge_coordinator_thread(): Remove some previous workarounds
for this bug.
innobase_start_or_create_for_mysql(): Set buf_page_cleaner_is_active
and srv_dict_stats_thread_active directly. Set srv_undo_sources before
starting the purge subsystem, to prevent immediate shutdown of the purge.
Create dict_stats_thread and fts_optimize_thread immediately
after setting srv_undo_sources, so that shutdown can use this flag to
determine if these subsystems were started.
dict_stats_shutdown(): Shut down dict_stats_thread. Backported from 10.2.
srv_shutdown_table_bg_threads(): Remove (unused).
2017-06-08 15:43:06 +03:00
|
|
|
|
|
|
|
/** Whether any undo log records can be generated */
|
MDEV-25791: Remove UNIV_INTERN
Back in 2006 or 2007, when MySQL AB and Innobase Oy existed as
separately controlled entities (Innobase had been acquired by
Oracle Corporation), MySQL 5.1 introduced a storage engine plugin
interface and Oracle made use of it by distributing a separate
InnoDB Plugin, which would contain some more bug fixes and
improvements, compared to the version of InnoDB that was statically
linked with the mysqld server that was distributed by MySQL AB.
The built-in InnoDB would export global symbols, which would clash
with the symbols of the dynamic InnoDB Plugin (which was supposed
to override the built-in one when present).
The solution to this problem was to declare all global symbols with
UNIV_INTERN, so that they would get the GCC function attribute that
specifies hidden visibility.
Later, in MariaDB Server, something based on Percona XtraDB (a fork of
MySQL InnoDB) became the statically linked implementation, and something
closer to MySQL InnoDB was available as a dynamic plugin. Starting with
version 10.2, MariaDB Server includes only one InnoDB implementation,
and hence any reason to have the UNIV_INTERN definition was lost.
btr_get_size_and_reserved(): Move to the same compilation unit with
the only caller.
innodb_set_buf_pool_size(): Remove. Modify innobase_buffer_pool_size
directly.
fil_crypt_calculate_checksum(): Merge to the only caller.
ha_innobase::innobase_reset_autoinc(): Merge to the only caller.
thd_query_start_micro(): Remove. Call thd_start_utime() directly.
2021-05-27 10:13:14 +03:00
|
|
|
bool srv_undo_sources;
|
2017-06-12 14:26:32 +03:00
|
|
|
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
/** innodb_encrypt_log */
|
|
|
|
my_bool srv_encrypt_log;
|
|
|
|
|
MDEV-11556 InnoDB redo log apply fails to adjust data file sizes
fil_space_t::recv_size: New member: recovered tablespace size in pages;
0 if no size change was read from the redo log,
or if the size change was implemented.
fil_space_set_recv_size(): New function for setting space->recv_size.
innodb_data_file_size_debug: A debug parameter for setting the system
tablespace size in recovery even when the redo log does not contain
any size changes. It is hard to write a small test case that would
cause the system tablespace to be extended at the critical moment.
recv_parse_log_rec(): Note those tablespaces whose size is being changed
by the redo log, by invoking fil_space_set_recv_size().
innobase_init(): Correct an error message, and do not require a larger
innodb_buffer_pool_size when starting up with a smaller innodb_page_size.
innobase_start_or_create_for_mysql(): Allow startup with any initial
size of the ibdata1 file if the autoextend attribute is set. Require
the minimum size of fixed-size system tablespaces to be 640 pages,
not 10 megabytes. Implement innodb_data_file_size_debug.
open_or_create_data_files(): Round the system tablespace size down
to pages, not to full megabytes, (Our test truncates the system
tablespace to more than 800 pages with innodb_page_size=4k.
InnoDB should not imagine that it was truncated to 768 pages
and then overwrite good pages in the tablespace.)
fil_flush_low(): Refactored from fil_flush().
fil_space_extend_must_retry(): Refactored from
fil_extend_space_to_desired_size().
fil_mutex_enter_and_prepare_for_io(): Extend the tablespace if
fil_space_set_recv_size() was called.
The test case has been successfully run with all the
innodb_page_size values 4k, 8k, 16k, 32k, 64k.
2016-12-28 12:05:43 +02:00
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
/** InnoDB system tablespace to set during recovery */
|
MDEV-25791: Remove UNIV_INTERN
Back in 2006 or 2007, when MySQL AB and Innobase Oy existed as
separately controlled entities (Innobase had been acquired by
Oracle Corporation), MySQL 5.1 introduced a storage engine plugin
interface and Oracle made use of it by distributing a separate
InnoDB Plugin, which would contain some more bug fixes and
improvements, compared to the version of InnoDB that was statically
linked with the mysqld server that was distributed by MySQL AB.
The built-in InnoDB would export global symbols, which would clash
with the symbols of the dynamic InnoDB Plugin (which was supposed
to override the built-in one when present).
The solution to this problem was to declare all global symbols with
UNIV_INTERN, so that they would get the GCC function attribute that
specifies hidden visibility.
Later, in MariaDB Server, something based on Percona XtraDB (a fork of
MySQL InnoDB) became the statically linked implementation, and something
closer to MySQL InnoDB was available as a dynamic plugin. Starting with
version 10.2, MariaDB Server includes only one InnoDB implementation,
and hence any reason to have the UNIV_INTERN definition was lost.
btr_get_size_and_reserved(): Move to the same compilation unit with
the only caller.
innodb_set_buf_pool_size(): Remove. Modify innobase_buffer_pool_size
directly.
fil_crypt_calculate_checksum(): Merge to the only caller.
ha_innobase::innobase_reset_autoinc(): Merge to the only caller.
thd_query_start_micro(): Remove. Call thd_start_utime() directly.
2021-05-27 10:13:14 +03:00
|
|
|
uint srv_sys_space_size_debug;
|
2020-01-12 02:05:28 +07:00
|
|
|
/** whether redo log file have been created at startup */
|
MDEV-25791: Remove UNIV_INTERN
Back in 2006 or 2007, when MySQL AB and Innobase Oy existed as
separately controlled entities (Innobase had been acquired by
Oracle Corporation), MySQL 5.1 introduced a storage engine plugin
interface and Oracle made use of it by distributing a separate
InnoDB Plugin, which would contain some more bug fixes and
improvements, compared to the version of InnoDB that was statically
linked with the mysqld server that was distributed by MySQL AB.
The built-in InnoDB would export global symbols, which would clash
with the symbols of the dynamic InnoDB Plugin (which was supposed
to override the built-in one when present).
The solution to this problem was to declare all global symbols with
UNIV_INTERN, so that they would get the GCC function attribute that
specifies hidden visibility.
Later, in MariaDB Server, something based on Percona XtraDB (a fork of
MySQL InnoDB) became the statically linked implementation, and something
closer to MySQL InnoDB was available as a dynamic plugin. Starting with
version 10.2, MariaDB Server includes only one InnoDB implementation,
and hence any reason to have the UNIV_INTERN definition was lost.
btr_get_size_and_reserved(): Move to the same compilation unit with
the only caller.
innodb_set_buf_pool_size(): Remove. Modify innobase_buffer_pool_size
directly.
fil_crypt_calculate_checksum(): Merge to the only caller.
ha_innobase::innobase_reset_autoinc(): Merge to the only caller.
thd_query_start_micro(): Remove. Call thd_start_utime() directly.
2021-05-27 10:13:14 +03:00
|
|
|
bool srv_log_file_created;
|
MDEV-11556 InnoDB redo log apply fails to adjust data file sizes
fil_space_t::recv_size: New member: recovered tablespace size in pages;
0 if no size change was read from the redo log,
or if the size change was implemented.
fil_space_set_recv_size(): New function for setting space->recv_size.
innodb_data_file_size_debug: A debug parameter for setting the system
tablespace size in recovery even when the redo log does not contain
any size changes. It is hard to write a small test case that would
cause the system tablespace to be extended at the critical moment.
recv_parse_log_rec(): Note those tablespaces whose size is being changed
by the redo log, by invoking fil_space_set_recv_size().
innobase_init(): Correct an error message, and do not require a larger
innodb_buffer_pool_size when starting up with a smaller innodb_page_size.
innobase_start_or_create_for_mysql(): Allow startup with any initial
size of the ibdata1 file if the autoextend attribute is set. Require
the minimum size of fixed-size system tablespaces to be 640 pages,
not 10 megabytes. Implement innodb_data_file_size_debug.
open_or_create_data_files(): Round the system tablespace size down
to pages, not to full megabytes, (Our test truncates the system
tablespace to more than 800 pages with innodb_page_size=4k.
InnoDB should not imagine that it was truncated to 768 pages
and then overwrite good pages in the tablespace.)
fil_flush_low(): Refactored from fil_flush().
fil_space_extend_must_retry(): Refactored from
fil_extend_space_to_desired_size().
fil_mutex_enter_and_prepare_for_io(): Extend the tablespace if
fil_space_set_recv_size() was called.
The test case has been successfully run with all the
innodb_page_size values 4k, 8k, 16k, 32k, 64k.
2016-12-28 12:05:43 +02:00
|
|
|
#endif /* UNIV_DEBUG */
|
2016-08-12 11:17:45 +03:00
|
|
|
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
/** whether some background threads that create redo log have been started */
|
|
|
|
static bool srv_started_redo;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
/** At a shutdown this value climbs from SRV_SHUTDOWN_NONE to
|
|
|
|
SRV_SHUTDOWN_CLEANUP and then to SRV_SHUTDOWN_LAST_PHASE, and so on */
|
2016-08-12 11:17:45 +03:00
|
|
|
enum srv_shutdown_t srv_shutdown_state = SRV_SHUTDOWN_NONE;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
/** Name of srv_monitor_file */
|
|
|
|
static char* srv_monitor_file_name;
|
2019-10-29 22:37:12 +01:00
|
|
|
std::unique_ptr<tpool::timer> srv_master_timer;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
/** */
|
|
|
|
#define SRV_MAX_N_PENDING_SYNC_IOS 100
|
|
|
|
|
|
|
|
#ifdef UNIV_PFS_THREAD
|
|
|
|
/* Keys to register InnoDB threads with performance schema */
|
2019-10-29 22:37:12 +01:00
|
|
|
mysql_pfs_key_t thread_pool_thread_key;
|
2014-02-26 19:11:54 +01:00
|
|
|
#endif /* UNIV_PFS_THREAD */
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
#ifdef HAVE_PSI_STAGE_INTERFACE
|
|
|
|
/** Array of all InnoDB stage events for monitoring activities via
|
|
|
|
performance schema. */
|
|
|
|
static PSI_stage_info* srv_stages[] =
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
2016-08-12 11:17:45 +03:00
|
|
|
&srv_stage_alter_table_end,
|
|
|
|
&srv_stage_alter_table_insert,
|
|
|
|
&srv_stage_alter_table_log_index,
|
|
|
|
&srv_stage_alter_table_log_table,
|
|
|
|
&srv_stage_alter_table_merge_sort,
|
|
|
|
&srv_stage_alter_table_read_pk_internal_sort,
|
|
|
|
&srv_stage_buffer_pool_load,
|
|
|
|
};
|
|
|
|
#endif /* HAVE_PSI_STAGE_INTERFACE */
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-02-14 19:49:54 +02:00
|
|
|
/** Delete any garbage log files */
|
|
|
|
static void delete_log_files()
|
|
|
|
{
|
|
|
|
for (size_t i= 1; i < 102; i++)
|
|
|
|
delete_log_file(std::to_string(i).c_str());
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
/** Creates log file.
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
@param create_new_db whether the database is being initialized
|
|
|
|
@param lsn log sequence number
|
|
|
|
@param logfile0 name of the log file
|
2016-08-12 11:17:45 +03:00
|
|
|
@return DB_SUCCESS or error code */
|
2022-02-14 19:49:54 +02:00
|
|
|
static dberr_t create_log_file(bool create_new_db, lsn_t lsn)
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
ut_ad(!srv_read_only_mode);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
/* We will retain ib_logfile0 until we have written a new logically
|
|
|
|
empty log as ib_logfile101 and atomically renamed it to
|
2022-02-14 19:49:54 +02:00
|
|
|
ib_logfile0 in log_t::rename_resized(). */
|
|
|
|
delete_log_files();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2023-04-12 13:49:57 +03:00
|
|
|
ut_ad(!os_aio_pending_reads());
|
|
|
|
ut_d(mysql_mutex_lock(&buf_pool.flush_list_mutex));
|
|
|
|
ut_ad(!buf_pool.get_oldest_modification(0));
|
|
|
|
ut_d(mysql_mutex_unlock(&buf_pool.flush_list_mutex));
|
2023-10-18 16:33:11 +03:00
|
|
|
/* os_aio_pending_writes() may hold here if some
|
|
|
|
write_io_callback() did not release the slot yet. However,
|
|
|
|
the page write itself must have completed, because the
|
|
|
|
buf_pool.flush_list is empty. In debug builds, we wait for
|
|
|
|
this to happen, hoping to get a hung process if this
|
|
|
|
assumption does not hold. */
|
|
|
|
ut_d(os_aio_wait_until_no_pending_writes(false));
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-02-10 16:37:12 +02:00
|
|
|
log_sys.latch.wr_lock(SRW_LOCK_CALL);
|
|
|
|
log_sys.set_capacity();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-02-14 19:49:54 +02:00
|
|
|
std::string logfile0{get_log_file_path("ib_logfile101")};
|
2020-01-12 02:05:28 +07:00
|
|
|
bool ret;
|
2022-02-15 15:03:15 +02:00
|
|
|
os_file_t file{
|
|
|
|
os_file_create_func(logfile0.c_str(),
|
|
|
|
OS_FILE_CREATE | OS_FILE_ON_ERROR_NO_EXIT,
|
|
|
|
OS_FILE_NORMAL, OS_LOG_FILE, false, &ret)
|
|
|
|
};
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
if (!ret) {
|
2022-02-14 19:49:54 +02:00
|
|
|
sql_print_error("InnoDB: Cannot create %.*s",
|
|
|
|
int(logfile0.size()), logfile0.data());
|
2022-02-10 16:37:12 +02:00
|
|
|
err_exit:
|
|
|
|
log_sys.latch.wr_unlock();
|
|
|
|
return DB_ERROR;
|
2020-01-12 02:05:28 +07:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
ret = os_file_set_size(logfile0.c_str(), file, srv_log_file_size);
|
|
|
|
if (!ret) {
|
|
|
|
ib::error() << "Cannot set log file " << logfile0
|
2021-12-03 12:12:14 +11:00
|
|
|
<< " size to " << ib::bytes_iec{srv_log_file_size};
|
2023-10-11 12:22:33 +03:00
|
|
|
close_and_exit:
|
|
|
|
os_file_close_func(file);
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
goto err_exit;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
log_sys.set_latest_format(srv_encrypt_log);
|
2023-10-11 12:22:33 +03:00
|
|
|
if (!log_sys.attach(file, srv_log_file_size)) {
|
|
|
|
goto close_and_exit;
|
|
|
|
}
|
2020-10-26 15:59:30 +02:00
|
|
|
if (!fil_system.sys_space->open(create_new_db)) {
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
goto err_exit;
|
2020-10-26 15:59:30 +02:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
/* Create a log checkpoint. */
|
2018-04-27 10:06:14 +03:00
|
|
|
if (log_sys.is_encrypted() && !log_crypt_init()) {
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
goto err_exit;
|
2017-02-10 12:11:42 +02:00
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
ut_d(recv_no_log_write = false);
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
log_sys.create(lsn);
|
2020-03-15 21:53:25 +03:00
|
|
|
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
ut_ad(srv_startup_is_before_trx_rollback_phase);
|
|
|
|
if (create_new_db) {
|
|
|
|
srv_startup_is_before_trx_rollback_phase = false;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Enable checkpoints in buf_flush_page_cleaner(). */
|
|
|
|
recv_sys.recovery_on = false;
|
2022-02-10 16:37:12 +02:00
|
|
|
log_sys.latch.wr_unlock();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2019-10-09 18:47:14 +03:00
|
|
|
log_make_checkpoint();
|
2021-07-16 11:27:41 +02:00
|
|
|
log_buffer_flush_to_disk();
|
2019-05-03 20:02:11 +03:00
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
return DB_SUCCESS;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2022-02-14 19:49:54 +02:00
|
|
|
/** Rename the redo log file after resizing.
|
|
|
|
@return whether an error occurred */
|
MDEV-27812 Allow SET GLOBAL innodb_log_file_size
We support online log resizing by replicating the current ib_logfile0
to a new file ib_logfile101, which will eventually replace the
ib_logfile0 on the first applicable log checkpoint.
Unless the log is located in a persistent memory file system (PMEM),
an attempt to SET GLOBAL innodb_log_file_size to less than
innodb_log_buffer_size will be refused. (With PMEM, a.k.a. mmap()
based log, that parameter has no meaning.)
Should the server be killed while the log was being resized,
both files ib_logfile0 and ib_logfile101 may exist on startup,
and since commit 3b06415cb8dfc2b10d9604950f6ed945bc016425
the extra file ib_logfile101 will be removed.
We will initiate checkpoint flushing by invoking buf_flush_ahead(),
to let buf_flush_page_cleaner() write out pages until the
buf_flush_async_lsn target has been reached.
On a log checkpoint, if the new checkpoint LSN is not older than
log_sys.resize_lsn (the start LSN of the ib_logfile101),
we can switch files and complete the log resizing. Else, we will
attempt to switch files on the next checkpoint.
Log resizing can be aborted by killing the connection that is
executing the SET GLOBAL statement.
If the ib_logfile101 wraps around to the beginning, we must
advance the log_sys.resize_lsn. In the resized log file,
the sequence bit will always be written as 1 (no wrap-around).
The log will be duplicated in log_t::resize_write(), invoked by
mtr_t::finish_write().
When the log is being written via system calls (not PMEM), the initial
log_sys.resize_lsn is the current log_sys.first_lsn, plus an integer
multiple of log_sys.block_size, corresponding to the LSN at the start
of the block that was written by log_sys.write_lsn. The log_sys.resize_buf
will be of the same size as the log_sys.buf. During resizing, the
contents of log_sys.buf and log_sys.resize_buf will be identical,
except that the sequence bit of each mini-transaction will always be 1 in
log_sys.resize_buf. If resizing is in progress, log_t::write_buf()
will write log_sys.resize_buf to log_sys.resize_log (ib_logfile101).
If the file would wrap around, the buffer will be written to
log_sys.START_OFFSET and the log_sys.resize_lsn advanced accordingly.
When using mmap() on /dev/shm or a PMEM mount -o dax file system,
the initial log_sys.resize_lsn will be the log_sys.lsn at the time
the resizing is initiated. If the log file wraps around during resizing,
then the log_sys.resize_lsn will be advanced by
(log_sys.resize_target - log_sys.START_OFFSET).
log_t::resize_start(), log_t::resize_abort(), log_t::write_checkpoint():
Unless the log is mmap() based, acquire flush_lock and write_lock.
In any case, acquire exclusive log_sys.latch to prevent race conditions.
log_t::resize_rename(): Renamed from log_t::rename_resized(),
and moved some code to the previous sole caller srv_start().
Thanks to Vladislav Vaintroub for helpful review comments
and to Matthias Leich for testing this, in particular, testing
crash recovery, multiple concurrent SET GLOBAL innodb_log_file_size
and frequently killed connections.
2022-03-02 16:53:04 +02:00
|
|
|
bool log_t::resize_rename() noexcept
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
2022-02-14 19:49:54 +02:00
|
|
|
std::string old_name{get_log_file_path("ib_logfile101")};
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
std::string new_name{get_log_file_path()};
|
2017-01-30 17:00:51 +02:00
|
|
|
|
2022-02-14 19:49:54 +02:00
|
|
|
if (IF_WIN(MoveFileEx(old_name.c_str(), new_name.c_str(),
|
MDEV-27812 Allow SET GLOBAL innodb_log_file_size
We support online log resizing by replicating the current ib_logfile0
to a new file ib_logfile101, which will eventually replace the
ib_logfile0 on the first applicable log checkpoint.
Unless the log is located in a persistent memory file system (PMEM),
an attempt to SET GLOBAL innodb_log_file_size to less than
innodb_log_buffer_size will be refused. (With PMEM, a.k.a. mmap()
based log, that parameter has no meaning.)
Should the server be killed while the log was being resized,
both files ib_logfile0 and ib_logfile101 may exist on startup,
and since commit 3b06415cb8dfc2b10d9604950f6ed945bc016425
the extra file ib_logfile101 will be removed.
We will initiate checkpoint flushing by invoking buf_flush_ahead(),
to let buf_flush_page_cleaner() write out pages until the
buf_flush_async_lsn target has been reached.
On a log checkpoint, if the new checkpoint LSN is not older than
log_sys.resize_lsn (the start LSN of the ib_logfile101),
we can switch files and complete the log resizing. Else, we will
attempt to switch files on the next checkpoint.
Log resizing can be aborted by killing the connection that is
executing the SET GLOBAL statement.
If the ib_logfile101 wraps around to the beginning, we must
advance the log_sys.resize_lsn. In the resized log file,
the sequence bit will always be written as 1 (no wrap-around).
The log will be duplicated in log_t::resize_write(), invoked by
mtr_t::finish_write().
When the log is being written via system calls (not PMEM), the initial
log_sys.resize_lsn is the current log_sys.first_lsn, plus an integer
multiple of log_sys.block_size, corresponding to the LSN at the start
of the block that was written by log_sys.write_lsn. The log_sys.resize_buf
will be of the same size as the log_sys.buf. During resizing, the
contents of log_sys.buf and log_sys.resize_buf will be identical,
except that the sequence bit of each mini-transaction will always be 1 in
log_sys.resize_buf. If resizing is in progress, log_t::write_buf()
will write log_sys.resize_buf to log_sys.resize_log (ib_logfile101).
If the file would wrap around, the buffer will be written to
log_sys.START_OFFSET and the log_sys.resize_lsn advanced accordingly.
When using mmap() on /dev/shm or a PMEM mount -o dax file system,
the initial log_sys.resize_lsn will be the log_sys.lsn at the time
the resizing is initiated. If the log file wraps around during resizing,
then the log_sys.resize_lsn will be advanced by
(log_sys.resize_target - log_sys.START_OFFSET).
log_t::resize_start(), log_t::resize_abort(), log_t::write_checkpoint():
Unless the log is mmap() based, acquire flush_lock and write_lock.
In any case, acquire exclusive log_sys.latch to prevent race conditions.
log_t::resize_rename(): Renamed from log_t::rename_resized(),
and moved some code to the previous sole caller srv_start().
Thanks to Vladislav Vaintroub for helpful review comments
and to Matthias Leich for testing this, in particular, testing
crash recovery, multiple concurrent SET GLOBAL innodb_log_file_size
and frequently killed connections.
2022-03-02 16:53:04 +02:00
|
|
|
MOVEFILE_REPLACE_EXISTING),
|
2022-02-14 19:49:54 +02:00
|
|
|
!rename(old_name.c_str(), new_name.c_str())))
|
|
|
|
return false;
|
2017-01-30 17:00:51 +02:00
|
|
|
|
MDEV-27812 Allow SET GLOBAL innodb_log_file_size
We support online log resizing by replicating the current ib_logfile0
to a new file ib_logfile101, which will eventually replace the
ib_logfile0 on the first applicable log checkpoint.
Unless the log is located in a persistent memory file system (PMEM),
an attempt to SET GLOBAL innodb_log_file_size to less than
innodb_log_buffer_size will be refused. (With PMEM, a.k.a. mmap()
based log, that parameter has no meaning.)
Should the server be killed while the log was being resized,
both files ib_logfile0 and ib_logfile101 may exist on startup,
and since commit 3b06415cb8dfc2b10d9604950f6ed945bc016425
the extra file ib_logfile101 will be removed.
We will initiate checkpoint flushing by invoking buf_flush_ahead(),
to let buf_flush_page_cleaner() write out pages until the
buf_flush_async_lsn target has been reached.
On a log checkpoint, if the new checkpoint LSN is not older than
log_sys.resize_lsn (the start LSN of the ib_logfile101),
we can switch files and complete the log resizing. Else, we will
attempt to switch files on the next checkpoint.
Log resizing can be aborted by killing the connection that is
executing the SET GLOBAL statement.
If the ib_logfile101 wraps around to the beginning, we must
advance the log_sys.resize_lsn. In the resized log file,
the sequence bit will always be written as 1 (no wrap-around).
The log will be duplicated in log_t::resize_write(), invoked by
mtr_t::finish_write().
When the log is being written via system calls (not PMEM), the initial
log_sys.resize_lsn is the current log_sys.first_lsn, plus an integer
multiple of log_sys.block_size, corresponding to the LSN at the start
of the block that was written by log_sys.write_lsn. The log_sys.resize_buf
will be of the same size as the log_sys.buf. During resizing, the
contents of log_sys.buf and log_sys.resize_buf will be identical,
except that the sequence bit of each mini-transaction will always be 1 in
log_sys.resize_buf. If resizing is in progress, log_t::write_buf()
will write log_sys.resize_buf to log_sys.resize_log (ib_logfile101).
If the file would wrap around, the buffer will be written to
log_sys.START_OFFSET and the log_sys.resize_lsn advanced accordingly.
When using mmap() on /dev/shm or a PMEM mount -o dax file system,
the initial log_sys.resize_lsn will be the log_sys.lsn at the time
the resizing is initiated. If the log file wraps around during resizing,
then the log_sys.resize_lsn will be advanced by
(log_sys.resize_target - log_sys.START_OFFSET).
log_t::resize_start(), log_t::resize_abort(), log_t::write_checkpoint():
Unless the log is mmap() based, acquire flush_lock and write_lock.
In any case, acquire exclusive log_sys.latch to prevent race conditions.
log_t::resize_rename(): Renamed from log_t::rename_resized(),
and moved some code to the previous sole caller srv_start().
Thanks to Vladislav Vaintroub for helpful review comments
and to Matthias Leich for testing this, in particular, testing
crash recovery, multiple concurrent SET GLOBAL innodb_log_file_size
and frequently killed connections.
2022-03-02 16:53:04 +02:00
|
|
|
sql_print_error("InnoDB: Failed to rename log from %.*s to %.*s (error %d)",
|
2022-02-14 19:49:54 +02:00
|
|
|
int(old_name.size()), old_name.data(),
|
MDEV-27812 Allow SET GLOBAL innodb_log_file_size
We support online log resizing by replicating the current ib_logfile0
to a new file ib_logfile101, which will eventually replace the
ib_logfile0 on the first applicable log checkpoint.
Unless the log is located in a persistent memory file system (PMEM),
an attempt to SET GLOBAL innodb_log_file_size to less than
innodb_log_buffer_size will be refused. (With PMEM, a.k.a. mmap()
based log, that parameter has no meaning.)
Should the server be killed while the log was being resized,
both files ib_logfile0 and ib_logfile101 may exist on startup,
and since commit 3b06415cb8dfc2b10d9604950f6ed945bc016425
the extra file ib_logfile101 will be removed.
We will initiate checkpoint flushing by invoking buf_flush_ahead(),
to let buf_flush_page_cleaner() write out pages until the
buf_flush_async_lsn target has been reached.
On a log checkpoint, if the new checkpoint LSN is not older than
log_sys.resize_lsn (the start LSN of the ib_logfile101),
we can switch files and complete the log resizing. Else, we will
attempt to switch files on the next checkpoint.
Log resizing can be aborted by killing the connection that is
executing the SET GLOBAL statement.
If the ib_logfile101 wraps around to the beginning, we must
advance the log_sys.resize_lsn. In the resized log file,
the sequence bit will always be written as 1 (no wrap-around).
The log will be duplicated in log_t::resize_write(), invoked by
mtr_t::finish_write().
When the log is being written via system calls (not PMEM), the initial
log_sys.resize_lsn is the current log_sys.first_lsn, plus an integer
multiple of log_sys.block_size, corresponding to the LSN at the start
of the block that was written by log_sys.write_lsn. The log_sys.resize_buf
will be of the same size as the log_sys.buf. During resizing, the
contents of log_sys.buf and log_sys.resize_buf will be identical,
except that the sequence bit of each mini-transaction will always be 1 in
log_sys.resize_buf. If resizing is in progress, log_t::write_buf()
will write log_sys.resize_buf to log_sys.resize_log (ib_logfile101).
If the file would wrap around, the buffer will be written to
log_sys.START_OFFSET and the log_sys.resize_lsn advanced accordingly.
When using mmap() on /dev/shm or a PMEM mount -o dax file system,
the initial log_sys.resize_lsn will be the log_sys.lsn at the time
the resizing is initiated. If the log file wraps around during resizing,
then the log_sys.resize_lsn will be advanced by
(log_sys.resize_target - log_sys.START_OFFSET).
log_t::resize_start(), log_t::resize_abort(), log_t::write_checkpoint():
Unless the log is mmap() based, acquire flush_lock and write_lock.
In any case, acquire exclusive log_sys.latch to prevent race conditions.
log_t::resize_rename(): Renamed from log_t::rename_resized(),
and moved some code to the previous sole caller srv_start().
Thanks to Vladislav Vaintroub for helpful review comments
and to Matthias Leich for testing this, in particular, testing
crash recovery, multiple concurrent SET GLOBAL innodb_log_file_size
and frequently killed connections.
2022-03-02 16:53:04 +02:00
|
|
|
int(new_name.size()), new_name.data(),
|
|
|
|
IF_WIN(int(GetLastError()), errno));
|
2022-02-14 19:49:54 +02:00
|
|
|
return true;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2019-12-04 15:00:57 +02:00
|
|
|
/** Create an undo tablespace file
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
@param[in] name file name
|
2016-08-12 11:17:45 +03:00
|
|
|
@return DB_SUCCESS or error code */
|
2019-12-04 15:00:57 +02:00
|
|
|
static dberr_t srv_undo_tablespace_create(const char* name)
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
2017-05-15 17:17:16 +03:00
|
|
|
pfs_os_file_t fh;
|
2016-08-12 11:17:45 +03:00
|
|
|
bool ret;
|
|
|
|
dberr_t err = DB_SUCCESS;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
os_file_create_subdirs_if_needed(name);
|
|
|
|
|
|
|
|
fh = os_file_create(
|
|
|
|
innodb_data_file_key,
|
|
|
|
name,
|
|
|
|
srv_read_only_mode ? OS_FILE_OPEN : OS_FILE_CREATE,
|
|
|
|
OS_FILE_NORMAL, OS_DATA_FILE, srv_read_only_mode, &ret);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2019-11-13 18:14:44 +01:00
|
|
|
if (!ret) {
|
2016-08-12 11:17:45 +03:00
|
|
|
if (os_file_get_last_error(false) != OS_FILE_ALREADY_EXISTS
|
2022-09-19 12:20:53 +03:00
|
|
|
#ifdef _AIX
|
2016-08-12 11:17:45 +03:00
|
|
|
/* AIX 5.1 after security patch ML7 may have
|
|
|
|
errno set to 0 here, which causes our function
|
|
|
|
to return 100; work around that AIX problem */
|
|
|
|
&& os_file_get_last_error(false) != 100
|
2022-09-19 12:20:53 +03:00
|
|
|
#endif
|
2016-08-12 11:17:45 +03:00
|
|
|
) {
|
|
|
|
ib::error() << "Can't create UNDO tablespace "
|
|
|
|
<< name;
|
|
|
|
}
|
|
|
|
err = DB_ERROR;
|
2019-11-13 18:14:44 +01:00
|
|
|
} else if (srv_read_only_mode) {
|
|
|
|
ib::info() << name << " opened in read-only mode";
|
2016-08-12 11:17:45 +03:00
|
|
|
} else {
|
|
|
|
/* We created the data file and now write it full of zeros */
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Data file " << name << " did not exist: new to"
|
|
|
|
" be created";
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Setting file " << name << " size to "
|
2021-12-03 12:12:14 +11:00
|
|
|
<< ib::bytes_iec{SRV_UNDO_TABLESPACE_SIZE_IN_PAGES
|
|
|
|
<< srv_page_size_shift};
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Database physically writes the file full: "
|
|
|
|
<< "wait...";
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2019-12-04 15:00:57 +02:00
|
|
|
if (!os_file_set_size(name, fh, os_offset_t
|
|
|
|
{SRV_UNDO_TABLESPACE_SIZE_IN_PAGES}
|
|
|
|
<< srv_page_size_shift)) {
|
|
|
|
ib::error() << "Unable to allocate " << name;
|
2016-08-12 11:17:45 +03:00
|
|
|
err = DB_ERROR;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
os_file_close(fh);
|
|
|
|
}
|
|
|
|
|
|
|
|
return(err);
|
|
|
|
}
|
2018-11-27 14:49:20 +02:00
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
inline dberr_t trx_sys_t::reset_page(mtr_t *mtr)
|
|
|
|
{
|
|
|
|
dberr_t err= DB_SUCCESS;
|
|
|
|
buf_block_t *sys_header= buf_page_get_gen(
|
|
|
|
page_id_t(TRX_SYS_SPACE, TRX_SYS_PAGE_NO), 0, RW_X_LATCH, nullptr,
|
|
|
|
BUF_GET, mtr, &err);
|
|
|
|
|
|
|
|
if (!sys_header) return err;
|
|
|
|
|
|
|
|
const bool dblwr_enabled=
|
|
|
|
mach_read_from_4(TRX_SYS_DOUBLEWRITE_MAGIC + TRX_SYS_DOUBLEWRITE +
|
|
|
|
sys_header->page.frame)
|
|
|
|
== TRX_SYS_DOUBLEWRITE_MAGIC_N;
|
|
|
|
|
|
|
|
char doublewrite[TRX_SYS_DOUBLEWRITE_BLOCK2 + 4];
|
|
|
|
memcpy(doublewrite, TRX_SYS_DOUBLEWRITE + sys_header->page.frame,
|
|
|
|
sizeof doublewrite);
|
|
|
|
|
|
|
|
fsp_init_file_page(fil_system.sys_space, sys_header, mtr);
|
|
|
|
|
|
|
|
mtr->write<2>(*sys_header, FIL_PAGE_TYPE + sys_header->page.frame,
|
|
|
|
FIL_PAGE_TYPE_TRX_SYS);
|
|
|
|
|
|
|
|
mtr->write<4>(*sys_header,
|
|
|
|
TRX_SYS + TRX_SYS_RSEGS + TRX_SYS_RSEG_PAGE_NO +
|
|
|
|
sys_header->page.frame, FSP_FIRST_RSEG_PAGE_NO);
|
|
|
|
mtr->memset(sys_header,
|
|
|
|
TRX_SYS + TRX_SYS_RSEGS + TRX_SYS_RSEG_SLOT_SIZE,
|
|
|
|
254 * TRX_SYS_RSEG_SLOT_SIZE, 0xff);
|
|
|
|
|
|
|
|
static_assert(TRX_SYS_RSEG_SLOT_SIZE == 8, "");
|
|
|
|
|
|
|
|
if (dblwr_enabled)
|
|
|
|
{
|
|
|
|
mtr->memcpy(
|
|
|
|
*sys_header, sys_header->page.frame + TRX_SYS_DOUBLEWRITE,
|
|
|
|
doublewrite, sizeof doublewrite);
|
|
|
|
mtr->memmove(
|
|
|
|
*sys_header,
|
|
|
|
TRX_SYS_DOUBLEWRITE + FSEG_HEADER_SIZE + TRX_SYS_DOUBLEWRITE_REPEAT,
|
|
|
|
TRX_SYS_DOUBLEWRITE + FSEG_HEADER_SIZE, 12);
|
|
|
|
memcpy(
|
|
|
|
sys_header->page.frame + TRX_SYS_DOUBLEWRITE
|
|
|
|
+ FSEG_HEADER_SIZE + TRX_SYS_DOUBLEWRITE_REPEAT,
|
|
|
|
sys_header->page.frame + TRX_SYS_DOUBLEWRITE + FSEG_HEADER_SIZE, 12);
|
|
|
|
}
|
|
|
|
|
|
|
|
return DB_SUCCESS;
|
|
|
|
}
|
|
|
|
|
|
|
|
/** Delete the old undo tablespaces present in the undo log directory */
|
|
|
|
static dberr_t srv_undo_delete_old_tablespaces()
|
|
|
|
{
|
|
|
|
/* Delete the old undo tablespaces*/
|
|
|
|
for (uint32_t i= 0; i < srv_undo_tablespaces_open; ++i)
|
|
|
|
fil_close_tablespace(srv_undo_space_id_start + i);
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("after_deleting_old_undo_abort", return DB_ERROR;);
|
|
|
|
|
|
|
|
/* Do checkpoint to get rid of old undo log tablespaces redo logs */
|
|
|
|
log_make_checkpoint();
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("after_deleting_old_undo_success", return DB_ERROR;);
|
|
|
|
|
|
|
|
return DB_SUCCESS;
|
|
|
|
}
|
|
|
|
|
|
|
|
/** Recreate the undo log tablespaces */
|
2023-03-03 11:38:43 +02:00
|
|
|
ATTRIBUTE_COLD static dberr_t srv_undo_tablespaces_reinit()
|
2022-10-24 20:46:43 +05:30
|
|
|
{
|
|
|
|
mtr_t mtr;
|
|
|
|
dberr_t err;
|
|
|
|
buf_block_t *first_rseg_hdr;
|
|
|
|
uint32_t latest_space_id;
|
|
|
|
|
|
|
|
mtr.start();
|
|
|
|
|
|
|
|
buf_block_t *dict_hdr= buf_page_get_gen(
|
|
|
|
page_id_t(DICT_HDR_SPACE, DICT_HDR_PAGE_NO), 0, RW_X_LATCH,
|
|
|
|
nullptr, BUF_GET, &mtr, &err);
|
|
|
|
|
|
|
|
if (!dict_hdr)
|
|
|
|
goto func_exit;
|
|
|
|
|
|
|
|
/* Assign the new space id for the first undo tablespace */
|
|
|
|
latest_space_id= mach_read_from_4(
|
|
|
|
DICT_HDR + DICT_HDR_MAX_SPACE_ID + dict_hdr->page.frame);
|
|
|
|
|
|
|
|
if (latest_space_id + srv_undo_tablespaces > SRV_SPACE_ID_UPPER_BOUND)
|
|
|
|
{
|
|
|
|
err= DB_ERROR;
|
|
|
|
sql_print_error("InnoDB: Running out of tablespace id");
|
|
|
|
goto func_exit;
|
|
|
|
}
|
|
|
|
|
|
|
|
first_rseg_hdr=
|
|
|
|
buf_page_get_gen(trx_sys.rseg_array[0].page_id(), 0, RW_X_LATCH,
|
|
|
|
nullptr, BUF_GET, &mtr, &err);
|
|
|
|
if (!first_rseg_hdr)
|
|
|
|
goto func_exit;
|
|
|
|
|
2023-03-03 11:38:43 +02:00
|
|
|
if (UNIV_UNLIKELY(mach_read_from_4(TRX_RSEG + TRX_RSEG_FORMAT +
|
|
|
|
first_rseg_hdr->page.frame)))
|
|
|
|
trx_rseg_format_upgrade(first_rseg_hdr, &mtr);
|
|
|
|
|
|
|
|
mtr.write<8,mtr_t::MAYBE_NOP>(*first_rseg_hdr,
|
|
|
|
TRX_RSEG + TRX_RSEG_MAX_TRX_ID +
|
|
|
|
first_rseg_hdr->page.frame,
|
|
|
|
trx_sys.get_max_trx_id() - 1);
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
/* Reset TRX_SYS page */
|
|
|
|
err= trx_sys.reset_page(&mtr);
|
|
|
|
|
|
|
|
if (err)
|
|
|
|
goto func_exit;
|
|
|
|
|
|
|
|
if (srv_undo_tablespaces_open == 0)
|
|
|
|
{
|
|
|
|
/* Free the system rollback segment */
|
|
|
|
for (ulint i= 1; i < TRX_SYS_N_RSEGS; i++)
|
|
|
|
{
|
|
|
|
trx_rseg_t *rseg= &trx_sys.rseg_array[i];
|
|
|
|
if (rseg->space != fil_system.sys_space)
|
|
|
|
continue;
|
|
|
|
buf_block_t *block= buf_page_get_gen(
|
|
|
|
rseg->page_id(), 0, RW_X_LATCH, nullptr, BUF_GET, &mtr);
|
|
|
|
if (!block) break;
|
|
|
|
while (!fseg_free_step(TRX_RSEG + TRX_RSEG_FSEG_HEADER +
|
|
|
|
block->page.frame, &mtr));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
for (ulint rseg_id= 1; rseg_id < TRX_SYS_N_RSEGS; rseg_id++)
|
|
|
|
{
|
|
|
|
trx_rseg_t *rseg= &trx_sys.rseg_array[rseg_id];
|
|
|
|
rseg->destroy();
|
|
|
|
rseg->init(nullptr, FIL_NULL);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (trx_sys.recovered_binlog_lsn
|
|
|
|
#ifdef WITH_WSREP
|
|
|
|
|| !trx_sys.recovered_wsrep_xid.is_null()
|
|
|
|
#endif /* WITH_WSREP */
|
|
|
|
)
|
|
|
|
{
|
|
|
|
/* Update binlog offset, binlog file name & wsrep xid in
|
|
|
|
system tablespace rollback segment */
|
|
|
|
if (trx_sys.recovered_binlog_lsn)
|
|
|
|
{
|
|
|
|
ut_d(const size_t len = strlen(trx_sys.recovered_binlog_filename) + 1);
|
|
|
|
ut_ad(len > 1);
|
|
|
|
ut_ad(len <= TRX_RSEG_BINLOG_NAME_LEN);
|
|
|
|
trx_rseg_update_binlog_offset(
|
|
|
|
first_rseg_hdr, trx_sys.recovered_binlog_filename,
|
|
|
|
trx_sys.recovered_binlog_offset, &mtr);
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef WITH_WSREP
|
|
|
|
if (!trx_sys.recovered_wsrep_xid.is_null())
|
|
|
|
trx_rseg_update_wsrep_checkpoint(
|
|
|
|
first_rseg_hdr, &trx_sys.recovered_wsrep_xid, &mtr);
|
|
|
|
#endif /* WITH_WSREP */
|
|
|
|
}
|
|
|
|
|
|
|
|
dict_hdr->page.fix();
|
|
|
|
|
|
|
|
mtr.commit();
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("after_rseg_reset_abort",
|
|
|
|
log_write_up_to(mtr.commit_lsn(), true);
|
|
|
|
dict_hdr->page.unfix();
|
|
|
|
return DB_ERROR;);
|
|
|
|
|
|
|
|
sql_print_information(
|
|
|
|
"InnoDB: Reinitializing innodb_undo_tablespaces= %u from %u",
|
|
|
|
srv_undo_tablespaces, srv_undo_tablespaces_open);
|
|
|
|
|
|
|
|
/* Delete the old undo tablespaces */
|
|
|
|
err= srv_undo_delete_old_tablespaces();
|
|
|
|
if (err)
|
|
|
|
{
|
|
|
|
dict_hdr->page.unfix();
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
mtr.start();
|
|
|
|
|
|
|
|
dict_hdr->page.lock.x_lock();
|
|
|
|
mtr.memo_push(dict_hdr, MTR_MEMO_PAGE_X_FIX);
|
|
|
|
|
|
|
|
if (srv_undo_tablespaces == 0)
|
|
|
|
{
|
|
|
|
srv_undo_space_id_start= 0;
|
|
|
|
srv_undo_tablespaces_open= 0;
|
|
|
|
goto func_exit;
|
|
|
|
}
|
|
|
|
|
|
|
|
srv_undo_space_id_start= latest_space_id;
|
|
|
|
if (fil_assign_new_space_id(&srv_undo_space_id_start))
|
|
|
|
mtr.write<4>(*dict_hdr, DICT_HDR + DICT_HDR_MAX_SPACE_ID
|
|
|
|
+ dict_hdr->page.frame, srv_undo_space_id_start);
|
|
|
|
|
|
|
|
/* Re-create the new undo tablespaces */
|
|
|
|
err= srv_undo_tablespaces_init(true, &mtr);
|
|
|
|
func_exit:
|
|
|
|
mtr.commit();
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("after_reinit_undo_abort",
|
|
|
|
log_write_up_to(mtr.commit_lsn(), true);
|
|
|
|
err= DB_ERROR;);
|
|
|
|
|
|
|
|
if (err == DB_SUCCESS)
|
|
|
|
{
|
|
|
|
/* Usually, recovery must work no matter when
|
|
|
|
log_checkpoints are triggered. This is a special case,
|
|
|
|
because this code is executed as part of InnoDB startup.
|
|
|
|
Backup requires that the server has been started up,
|
|
|
|
backup should never observe the log records that
|
|
|
|
were written in mtr and also srv_undo_tablespaces_init()
|
|
|
|
initializes the undo tablespace start id based on page0
|
|
|
|
content before reading the redo log */
|
|
|
|
log_make_checkpoint();
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("after_reinit_undo_success", err= DB_ERROR;);
|
|
|
|
srv_undo_tablespaces_active= srv_undo_tablespaces;
|
|
|
|
}
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
/** Reinitialize the undo tablespaces when there is no undo log
|
|
|
|
left to purge/rollback and validate the number of undo opened
|
|
|
|
undo tablespace and user given undo tablespace
|
2019-12-04 15:00:57 +02:00
|
|
|
@return DB_SUCCESS if it is valid */
|
2022-10-24 20:46:43 +05:30
|
|
|
static dberr_t srv_undo_tablespaces_reinitialize()
|
2016-08-12 11:17:45 +03:00
|
|
|
{
|
2022-10-24 20:46:43 +05:30
|
|
|
|
|
|
|
/* Re-create the undo tablespaces if it has no undo logs
|
|
|
|
left to purge/rollback */
|
|
|
|
if (srv_undo_tablespaces != srv_undo_tablespaces_open &&
|
|
|
|
trx_sys.is_undo_empty())
|
|
|
|
return srv_undo_tablespaces_reinit();
|
|
|
|
|
2019-12-04 15:00:57 +02:00
|
|
|
/* If the user says that there are fewer than what we find we
|
|
|
|
tolerate that discrepancy but not the inverse. Because there could
|
|
|
|
be unused undo tablespaces for future use. */
|
|
|
|
|
2022-12-05 16:25:27 +05:30
|
|
|
if (srv_undo_tablespaces != srv_undo_tablespaces_open)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
2022-10-24 20:46:43 +05:30
|
|
|
sql_print_warning("InnoDB: Cannot change innodb_undo_tablespaces=%u "
|
|
|
|
"because previous shutdown was not with "
|
|
|
|
"innodb_fast_shutdown=0", srv_undo_tablespaces);
|
2022-12-05 16:25:27 +05:30
|
|
|
srv_undo_tablespaces= srv_undo_tablespaces_open;
|
|
|
|
}
|
2019-12-04 15:00:57 +02:00
|
|
|
else if (srv_undo_tablespaces_open > 0)
|
2022-10-24 20:46:43 +05:30
|
|
|
sql_print_information("InnoDB: Opened " UINT32PF " undo tablespaces",
|
|
|
|
srv_undo_tablespaces_open);
|
2019-12-04 15:00:57 +02:00
|
|
|
|
|
|
|
return DB_SUCCESS;
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2019-12-04 15:00:57 +02:00
|
|
|
/** @return the number of active undo tablespaces (except system tablespace) */
|
2021-07-22 11:22:47 +03:00
|
|
|
static uint32_t trx_rseg_get_n_undo_tablespaces()
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
|
|
|
std::set<uint32_t> space_ids;
|
|
|
|
mtr_t mtr;
|
|
|
|
mtr.start();
|
|
|
|
|
2023-12-04 09:45:53 +02:00
|
|
|
if (const buf_block_t *sys_header=
|
|
|
|
recv_sys.recover({TRX_SYS_SPACE, TRX_SYS_PAGE_NO}, &mtr, nullptr))
|
2019-12-04 15:00:57 +02:00
|
|
|
for (ulint rseg_id= 0; rseg_id < TRX_SYS_N_RSEGS; rseg_id++)
|
|
|
|
if (trx_sysf_rseg_get_page_no(sys_header, rseg_id) != FIL_NULL)
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
if (uint32_t space= trx_sysf_rseg_get_space(sys_header, rseg_id))
|
|
|
|
space_ids.insert(space);
|
2019-12-04 15:00:57 +02:00
|
|
|
mtr.commit();
|
2021-07-22 11:22:47 +03:00
|
|
|
return static_cast<uint32_t>(space_ids.size());
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
2018-11-27 14:49:20 +02:00
|
|
|
|
2019-12-04 15:00:57 +02:00
|
|
|
/** Open an undo tablespace.
|
|
|
|
@param[in] create whether undo tablespaces are being created
|
|
|
|
@param[in] name tablespace file name
|
|
|
|
@param[in] i undo tablespace count
|
|
|
|
@return undo tablespace identifier
|
2023-10-19 14:35:31 +03:00
|
|
|
@retval 0 if file doesn't exist
|
|
|
|
@retval ~0U if page0 is corrupted */
|
|
|
|
static uint32_t srv_undo_tablespace_open(bool create, const char* name,
|
2021-07-22 11:22:47 +03:00
|
|
|
uint32_t i)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
|
|
|
bool success;
|
2021-07-22 11:22:47 +03:00
|
|
|
uint32_t space_id= 0;
|
|
|
|
uint32_t fsp_flags= 0;
|
2019-12-04 15:00:57 +02:00
|
|
|
|
|
|
|
if (create)
|
|
|
|
{
|
|
|
|
space_id= srv_undo_space_id_start + i;
|
|
|
|
switch (srv_checksum_algorithm) {
|
|
|
|
case SRV_CHECKSUM_ALGORITHM_FULL_CRC32:
|
|
|
|
case SRV_CHECKSUM_ALGORITHM_STRICT_FULL_CRC32:
|
|
|
|
fsp_flags= FSP_FLAGS_FCRC32_MASK_MARKER | FSP_FLAGS_FCRC32_PAGE_SSIZE();
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
fsp_flags= FSP_FLAGS_PAGE_SSIZE();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-12-04 20:01:04 +02:00
|
|
|
pfs_os_file_t fh= os_file_create(innodb_data_file_key, name, OS_FILE_OPEN |
|
|
|
|
OS_FILE_ON_ERROR_NO_EXIT |
|
|
|
|
OS_FILE_ON_ERROR_SILENT,
|
|
|
|
OS_FILE_AIO, OS_DATA_FILE,
|
|
|
|
srv_read_only_mode, &success);
|
2019-12-04 15:00:57 +02:00
|
|
|
|
|
|
|
if (!success)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
os_offset_t size= os_file_get_size(fh);
|
|
|
|
ut_a(size != os_offset_t(-1));
|
|
|
|
|
|
|
|
if (!create)
|
|
|
|
{
|
|
|
|
page_t *page= static_cast<byte*>(aligned_malloc(srv_page_size,
|
|
|
|
srv_page_size));
|
2023-10-19 13:50:00 +03:00
|
|
|
if (os_file_read(IORequestRead, fh, page, 0, srv_page_size, nullptr) !=
|
2023-10-17 18:37:45 +05:30
|
|
|
DB_SUCCESS)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
|
|
|
err_exit:
|
|
|
|
ib::error() << "Unable to read first page of file " << name;
|
|
|
|
aligned_free(page);
|
2023-10-19 14:35:31 +03:00
|
|
|
return ~0U;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
|
2019-12-04 20:01:04 +02:00
|
|
|
uint32_t id= mach_read_from_4(FIL_PAGE_SPACE_ID + page);
|
2019-11-25 22:32:24 +07:00
|
|
|
if (id == 0 || id >= SRV_SPACE_ID_UPPER_BOUND ||
|
2020-01-21 22:22:48 +08:00
|
|
|
memcmp_aligned<2>(FIL_PAGE_SPACE_ID + page,
|
2019-12-04 20:01:04 +02:00
|
|
|
FSP_HEADER_OFFSET + FSP_SPACE_ID + page, 4))
|
|
|
|
{
|
|
|
|
ib::error() << "Inconsistent tablespace ID in file " << name;
|
|
|
|
goto err_exit;
|
|
|
|
}
|
|
|
|
|
2023-10-17 18:37:45 +05:30
|
|
|
space_id= id;
|
2019-12-04 20:01:04 +02:00
|
|
|
fsp_flags= mach_read_from_4(FSP_HEADER_OFFSET + FSP_SPACE_FLAGS + page);
|
2023-10-19 13:50:00 +03:00
|
|
|
|
2019-12-04 20:01:04 +02:00
|
|
|
if (buf_page_is_corrupted(false, page, fsp_flags))
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
2023-10-19 13:50:00 +03:00
|
|
|
sql_print_error("InnoDB: Checksum mismatch in the first page of file %s",
|
|
|
|
name);
|
2023-10-17 18:37:45 +05:30
|
|
|
if (recv_sys.dblwr.restore_first_page(space_id, name, fh))
|
|
|
|
goto err_exit;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
aligned_free(page);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Load the tablespace into InnoDB's internal data structures. */
|
|
|
|
|
|
|
|
/* We set the biggest space id to the undo tablespace
|
|
|
|
because InnoDB hasn't opened any other tablespace apart
|
|
|
|
from the system tablespace. */
|
|
|
|
|
|
|
|
fil_set_max_space_id_if_bigger(space_id);
|
|
|
|
|
2023-04-19 18:56:58 +03:00
|
|
|
mysql_mutex_lock(&fil_system.mutex);
|
MDEV-25312 Replace fil_space_t::name with fil_space_t::name()
A consistency check for fil_space_t::name is causing recovery failures
in MDEV-25180 (Atomic ALTER TABLE). So, we'd better remove that field
altogether.
fil_space_t::name was more or less a copy of dict_table_t::name
(except for some special cases), and it was not being used for
anything useful.
There used to be a name_hash, but it had been removed already in
commit a75dbfd7183cc96680f3e3e684fd36500dac8158 (MDEV-12266).
We will also remove os_normalize_path(), OS_PATH_SEPARATOR,
OS_PATH_SEPATOR_ALT. On Microsoft Windows, we will treat \ and /
roughly in the same way. The intention is that for per-table
tablespaces, the filenames will always follow the pattern
prefix/databasename/tablename.ibd. (Any \ in the prefix must not
be converted.)
ut_basename_noext(): Remove (unused function).
read_link_file(): Replaces RemoteDatafile::read_link_file().
We will ensure that the last two path component separators are
forward slashes (converting up to 2 trailing backslashes on
Microsoft Windows), so that everywhere else we can
assume that data file names end in "/databasename/tablename.ibd".
Note: On Microsoft Windows, path names that start with \\?\ must
not contain / as path component separators. Previously, such paths
did work in the DATA DIRECTORY argument of InnoDB tables.
Reviewed by: Vladislav Vaintroub
2021-04-07 18:01:13 +03:00
|
|
|
fil_space_t *space= fil_space_t::create(space_id, fsp_flags,
|
2023-03-16 18:11:37 +02:00
|
|
|
FIL_TYPE_TABLESPACE, nullptr,
|
|
|
|
FIL_ENCRYPTION_DEFAULT, true);
|
2023-04-19 18:56:58 +03:00
|
|
|
ut_ad(space);
|
2019-12-04 15:00:57 +02:00
|
|
|
fil_node_t *file= space->add(name, fh, 0, false, true);
|
|
|
|
|
|
|
|
if (create)
|
|
|
|
{
|
2020-10-26 15:59:30 +02:00
|
|
|
space->set_sizes(SRV_UNDO_TABLESPACE_SIZE_IN_PAGES);
|
2020-10-15 16:28:19 +03:00
|
|
|
space->size= file->size= uint32_t(size >> srv_page_size_shift);
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
2020-10-26 15:59:30 +02:00
|
|
|
else if (!file->read_page0())
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
2020-10-26 15:59:30 +02:00
|
|
|
os_file_close(file->handle);
|
|
|
|
file->handle= OS_FILE_CLOSED;
|
|
|
|
ut_a(fil_system.n_open > 0);
|
|
|
|
fil_system.n_open--;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
|
2020-12-04 19:02:58 +02:00
|
|
|
mysql_mutex_unlock(&fil_system.mutex);
|
2019-12-04 15:00:57 +02:00
|
|
|
return space_id;
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
2015-06-16 10:57:05 +02:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
/** Check if undo tablespaces and redo log files exist before creating a
|
|
|
|
new system tablespace
|
|
|
|
@retval DB_SUCCESS if all undo and redo logs are not found
|
|
|
|
@retval DB_ERROR if any undo and redo logs are found */
|
|
|
|
static
|
|
|
|
dberr_t
|
|
|
|
srv_check_undo_redo_logs_exists()
|
|
|
|
{
|
|
|
|
bool ret;
|
2022-02-15 15:03:15 +02:00
|
|
|
os_file_t fh;
|
2016-08-12 11:17:45 +03:00
|
|
|
char name[OS_FILE_MAX_PATH];
|
2015-06-16 10:57:05 +02:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
/* Check if any undo tablespaces exist */
|
|
|
|
for (ulint i = 1; i <= srv_undo_tablespaces; ++i) {
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-25312 Replace fil_space_t::name with fil_space_t::name()
A consistency check for fil_space_t::name is causing recovery failures
in MDEV-25180 (Atomic ALTER TABLE). So, we'd better remove that field
altogether.
fil_space_t::name was more or less a copy of dict_table_t::name
(except for some special cases), and it was not being used for
anything useful.
There used to be a name_hash, but it had been removed already in
commit a75dbfd7183cc96680f3e3e684fd36500dac8158 (MDEV-12266).
We will also remove os_normalize_path(), OS_PATH_SEPARATOR,
OS_PATH_SEPATOR_ALT. On Microsoft Windows, we will treat \ and /
roughly in the same way. The intention is that for per-table
tablespaces, the filenames will always follow the pattern
prefix/databasename/tablename.ibd. (Any \ in the prefix must not
be converted.)
ut_basename_noext(): Remove (unused function).
read_link_file(): Replaces RemoteDatafile::read_link_file().
We will ensure that the last two path component separators are
forward slashes (converting up to 2 trailing backslashes on
Microsoft Windows), so that everywhere else we can
assume that data file names end in "/databasename/tablename.ibd".
Note: On Microsoft Windows, path names that start with \\?\ must
not contain / as path component separators. Previously, such paths
did work in the DATA DIRECTORY argument of InnoDB tables.
Reviewed by: Vladislav Vaintroub
2021-04-07 18:01:13 +03:00
|
|
|
snprintf(name, sizeof name, "%s/undo%03zu", srv_undo_dir, i);
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2022-02-15 15:03:15 +02:00
|
|
|
fh = os_file_create_func(
|
|
|
|
name,
|
2016-08-12 11:17:45 +03:00
|
|
|
OS_FILE_OPEN_RETRY
|
|
|
|
| OS_FILE_ON_ERROR_NO_EXIT
|
|
|
|
| OS_FILE_ON_ERROR_SILENT,
|
|
|
|
OS_FILE_NORMAL,
|
|
|
|
OS_DATA_FILE,
|
|
|
|
srv_read_only_mode,
|
|
|
|
&ret);
|
|
|
|
|
|
|
|
if (ret) {
|
2022-02-15 15:03:15 +02:00
|
|
|
os_file_close_func(fh);
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::error()
|
|
|
|
<< "undo tablespace '" << name << "' exists."
|
|
|
|
" Creating system tablespace with existing undo"
|
|
|
|
" tablespaces is not supported. Please delete"
|
|
|
|
" all undo tablespaces before creating new"
|
|
|
|
" system tablespace.";
|
|
|
|
return(DB_ERROR);
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
/* Check if redo log file exists */
|
|
|
|
auto logfilename = get_log_file_path();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-02-15 15:03:15 +02:00
|
|
|
fh = os_file_create_func(logfilename.c_str(),
|
|
|
|
OS_FILE_OPEN_RETRY | OS_FILE_ON_ERROR_NO_EXIT
|
|
|
|
| OS_FILE_ON_ERROR_SILENT,
|
|
|
|
OS_FILE_NORMAL, OS_LOG_FILE,
|
|
|
|
srv_read_only_mode, &ret);
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
if (ret) {
|
2022-02-15 15:03:15 +02:00
|
|
|
os_file_close_func(fh);
|
2020-01-12 02:05:28 +07:00
|
|
|
ib::error() << "redo log file '" << logfilename
|
|
|
|
<< "' exists. Creating system tablespace with"
|
|
|
|
" existing redo log file is not recommended."
|
|
|
|
" Please delete redo log file before"
|
|
|
|
" creating new system tablespace.";
|
|
|
|
return DB_ERROR;
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
return(DB_SUCCESS);
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
static dberr_t srv_all_undo_tablespaces_open(bool create_new_undo,
|
|
|
|
uint32_t n_undo)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
|
|
|
/* Open all the undo tablespaces that are currently in use. If we
|
|
|
|
fail to open any of these it is a fatal error. The tablespace ids
|
|
|
|
should be contiguous. It is a fatal error because they are required
|
|
|
|
for recovery and are referenced by the UNDO logs (a.k.a RBS). */
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
uint32_t prev_id= create_new_undo ? srv_undo_space_id_start - 1 : 0;
|
2019-12-04 15:00:57 +02:00
|
|
|
|
2021-07-22 11:22:47 +03:00
|
|
|
for (uint32_t i= 0; i < n_undo; ++i)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
|
|
|
char name[OS_FILE_MAX_PATH];
|
2021-07-22 11:22:47 +03:00
|
|
|
snprintf(name, sizeof name, "%s/undo%03u", srv_undo_dir, i + 1);
|
2022-10-24 20:46:43 +05:30
|
|
|
uint32_t space_id= srv_undo_tablespace_open(create_new_undo, name, i);
|
2023-10-17 18:37:45 +05:30
|
|
|
switch (space_id) {
|
2023-10-19 14:35:31 +03:00
|
|
|
case ~0U:
|
2023-10-17 18:37:45 +05:30
|
|
|
return DB_CORRUPTION;
|
|
|
|
case 0:
|
2022-10-24 20:46:43 +05:30
|
|
|
if (!create_new_undo)
|
2023-10-17 18:37:45 +05:30
|
|
|
goto unused_undo;
|
2023-10-19 14:35:31 +03:00
|
|
|
sql_print_error("InnoDB: Unable to open create tablespace '%s'.", name);
|
2019-12-04 15:00:57 +02:00
|
|
|
return DB_ERROR;
|
2023-10-17 18:37:45 +05:30
|
|
|
default:
|
|
|
|
/* Should be no gaps in undo tablespace ids. */
|
|
|
|
ut_a(!i || prev_id + 1 == space_id);
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
prev_id= space_id;
|
|
|
|
|
|
|
|
/* Note the first undo tablespace id in case of
|
|
|
|
no active undo tablespace. */
|
|
|
|
if (0 == srv_undo_tablespaces_open++)
|
|
|
|
srv_undo_space_id_start= space_id;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Open any extra unused undo tablespaces. These must be contiguous.
|
|
|
|
We stop at the first failure. These are undo tablespaces that are
|
|
|
|
not in use and therefore not required by recovery. We only check
|
|
|
|
that there are no gaps. */
|
2023-10-17 18:37:45 +05:30
|
|
|
unused_undo:
|
2021-07-22 11:22:47 +03:00
|
|
|
for (uint32_t i= prev_id + 1; i < srv_undo_space_id_start + TRX_SYS_N_RSEGS;
|
2019-12-04 15:00:57 +02:00
|
|
|
++i)
|
|
|
|
{
|
|
|
|
char name[OS_FILE_MAX_PATH];
|
2021-07-22 11:22:47 +03:00
|
|
|
snprintf(name, sizeof name, "%s/undo%03u", srv_undo_dir, i);
|
2022-11-29 16:23:46 +05:30
|
|
|
uint32_t space_id= srv_undo_tablespace_open(create_new_undo, name, i);
|
2023-10-19 14:35:31 +03:00
|
|
|
if (!space_id || space_id == ~0U)
|
2019-12-04 15:00:57 +02:00
|
|
|
break;
|
2022-11-29 16:23:46 +05:30
|
|
|
if (0 == srv_undo_tablespaces_open++)
|
|
|
|
srv_undo_space_id_start= space_id;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
return DB_SUCCESS;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
|
MDEV-12289 Keep 128 persistent rollback segments for compatibility and performance
InnoDB divides the allocation of undo logs into rollback segments.
The DB_ROLL_PTR system column of clustered indexes can address up to
128 rollback segments (TRX_SYS_N_RSEGS). Originally, InnoDB only
created one rollback segment. In MySQL 5.5 or in the InnoDB Plugin
for MySQL 5.1, all 128 rollback segments were created.
MySQL 5.7 hard-codes the rollback segment IDs 1..32 for temporary undo logs.
On upgrade, unless a slow shutdown (innodb_fast_shutdown=0)
was performed on the old server instance, these rollback segments
could be in use by transactions that are in XA PREPARE state or
transactions that were left behind by a server kill followed by a
normal shutdown immediately after restart.
Persistent tables cannot refer to temporary undo logs or vice versa.
Therefore, we should keep two distinct sets of rollback segments:
one for persistent tables and another for temporary tables. In this way,
all 128 rollback segments will be available for both types of tables,
which could improve performance. Also, MariaDB 10.2 will remain more
compatible than MySQL 5.7 with data files from earlier versions of
MySQL or MariaDB.
trx_sys_t::temp_rsegs[TRX_SYS_N_RSEGS]: A new array of temporary
rollback segments. The trx_sys_t::rseg_array[TRX_SYS_N_RSEGS] will
be solely for persistent undo logs.
srv_tmp_undo_logs. Remove. Use the constant TRX_SYS_N_RSEGS.
srv_available_undo_logs: Change the type to ulong.
trx_rseg_get_on_id(): Remove. Instead, let the callers refer to
trx_sys directly.
trx_rseg_create(), trx_sysf_rseg_find_free(): Remove unneeded parameters.
These functions only deal with persistent undo logs.
trx_temp_rseg_create(): New function, to create all temporary rollback
segments at server startup.
trx_rseg_t::is_persistent(): Determine if the rollback segment is for
persistent tables.
trx_sys_is_noredo_rseg_slot(): Remove. The callers must know based on
context (such as table handle) whether the DB_ROLL_PTR is referring to
a persistent undo log.
trx_sys_create_rsegs(): Remove all parameters, which were always passed
as global variables. Instead, modify the global variables directly.
enum trx_rseg_type_t: Remove.
trx_t::get_temp_rseg(): A method to ensure that a temporary
rollback segment has been assigned for the transaction.
trx_t::assign_temp_rseg(): Replaces trx_assign_rseg().
trx_purge_free_segment(), trx_purge_truncate_rseg_history():
Remove the redundant variable noredo=false.
Temporary undo logs are discarded immediately at transaction commit
or rollback, not lazily by purge.
trx_purge_mark_undo_for_truncate(): Remove references to the
temporary rollback segments.
trx_purge_mark_undo_for_truncate(): Remove a check for temporary
rollback segments. Only the dedicated persistent undo log tablespaces
can be truncated.
trx_undo_get_undo_rec_low(), trx_undo_get_undo_rec(): Add the
parameter is_temp.
trx_rseg_mem_restore(): Split from trx_rseg_mem_create().
Initialize the undo log and the rollback segment from the file
data structures.
trx_sysf_get_n_rseg_slots(): Renamed from
trx_sysf_used_slots_for_redo_rseg(). Count the persistent
rollback segment headers that have been initialized.
trx_sys_close(): Also free trx_sys->temp_rsegs[].
get_next_redo_rseg(): Merged to trx_assign_rseg_low().
trx_assign_rseg_low(): Remove the parameters and access the
global variables directly. Revert to simple round-robin, now that
the whole trx_sys->rseg_array[] is for persistent undo log again.
get_next_noredo_rseg(): Moved to trx_t::assign_temp_rseg().
srv_undo_tablespaces_init(): Remove some parameters and use the
global variables directly. Clarify some error messages.
Adjust the test innodb.log_file. Apparently, before these changes,
InnoDB somehow ignored missing dedicated undo tablespace files that
are pointed by the TRX_SYS header page, possibly losing part of
essential transaction system state.
2017-03-30 13:11:34 +03:00
|
|
|
/** Open the configured number of dedicated undo tablespaces.
|
2022-10-24 20:46:43 +05:30
|
|
|
@param[in] create_new_undo whether the undo tablespaces has to be created
|
|
|
|
@param[in,out] mtr mini-transaction
|
2016-08-12 11:17:45 +03:00
|
|
|
@return DB_SUCCESS or error code */
|
2022-10-24 20:46:43 +05:30
|
|
|
dberr_t srv_undo_tablespaces_init(bool create_new_undo, mtr_t *mtr)
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
2019-12-04 15:00:57 +02:00
|
|
|
srv_undo_tablespaces_open= 0;
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
ut_ad(!create_new_undo || mtr);
|
2019-12-04 15:00:57 +02:00
|
|
|
ut_a(srv_undo_tablespaces <= TRX_SYS_N_RSEGS);
|
2023-04-14 13:08:28 +03:00
|
|
|
ut_a(!create_new_undo || srv_operation <= SRV_OPERATION_EXPORT_RESTORED);
|
2019-12-04 15:00:57 +02:00
|
|
|
|
|
|
|
if (srv_undo_tablespaces == 1)
|
|
|
|
srv_undo_tablespaces= 0;
|
|
|
|
|
|
|
|
/* Create the undo spaces only if we are creating a new
|
|
|
|
instance. We don't allow creating of new undo tablespaces
|
|
|
|
in an existing instance (yet). */
|
2022-10-24 20:46:43 +05:30
|
|
|
if (create_new_undo)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
|
|
|
DBUG_EXECUTE_IF("innodb_undo_upgrade", srv_undo_space_id_start= 3;);
|
|
|
|
|
|
|
|
for (ulint i= 0; i < srv_undo_tablespaces; ++i)
|
|
|
|
{
|
|
|
|
char name[OS_FILE_MAX_PATH];
|
MDEV-25312 Replace fil_space_t::name with fil_space_t::name()
A consistency check for fil_space_t::name is causing recovery failures
in MDEV-25180 (Atomic ALTER TABLE). So, we'd better remove that field
altogether.
fil_space_t::name was more or less a copy of dict_table_t::name
(except for some special cases), and it was not being used for
anything useful.
There used to be a name_hash, but it had been removed already in
commit a75dbfd7183cc96680f3e3e684fd36500dac8158 (MDEV-12266).
We will also remove os_normalize_path(), OS_PATH_SEPARATOR,
OS_PATH_SEPATOR_ALT. On Microsoft Windows, we will treat \ and /
roughly in the same way. The intention is that for per-table
tablespaces, the filenames will always follow the pattern
prefix/databasename/tablename.ibd. (Any \ in the prefix must not
be converted.)
ut_basename_noext(): Remove (unused function).
read_link_file(): Replaces RemoteDatafile::read_link_file().
We will ensure that the last two path component separators are
forward slashes (converting up to 2 trailing backslashes on
Microsoft Windows), so that everywhere else we can
assume that data file names end in "/databasename/tablename.ibd".
Note: On Microsoft Windows, path names that start with \\?\ must
not contain / as path component separators. Previously, such paths
did work in the DATA DIRECTORY argument of InnoDB tables.
Reviewed by: Vladislav Vaintroub
2021-04-07 18:01:13 +03:00
|
|
|
snprintf(name, sizeof name, "%s/undo%03zu", srv_undo_dir, i + 1);
|
2019-12-04 15:00:57 +02:00
|
|
|
if (dberr_t err= srv_undo_tablespace_create(name))
|
|
|
|
{
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
ib::error() << "Could not create undo tablespace '" << name << "'.";
|
|
|
|
return err;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Get the tablespace ids of all the undo segments excluding
|
|
|
|
the system tablespace (0). If we are creating a new instance then
|
|
|
|
we build the undo_tablespace_ids ourselves since they don't
|
|
|
|
already exist. */
|
|
|
|
srv_undo_tablespaces_active= srv_undo_tablespaces;
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
uint32_t n_undo= (create_new_undo || srv_operation == SRV_OPERATION_BACKUP ||
|
|
|
|
srv_operation == SRV_OPERATION_RESTORE_DELTA)
|
2019-12-04 15:00:57 +02:00
|
|
|
? srv_undo_tablespaces : TRX_SYS_N_RSEGS;
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
if (dberr_t err= srv_all_undo_tablespaces_open(create_new_undo, n_undo))
|
2019-12-04 15:00:57 +02:00
|
|
|
return err;
|
|
|
|
|
|
|
|
/* Initialize srv_undo_space_id_start=0 when there are no
|
|
|
|
dedicated undo tablespaces. */
|
|
|
|
if (srv_undo_tablespaces_open == 0)
|
|
|
|
srv_undo_space_id_start= 0;
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
if (create_new_undo)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
2021-07-22 11:22:47 +03:00
|
|
|
for (uint32_t i= 0; i < srv_undo_tablespaces; ++i)
|
2019-12-04 15:00:57 +02:00
|
|
|
{
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
dberr_t err= fsp_header_init(fil_space_get(srv_undo_space_id_start + i),
|
2022-10-24 20:46:43 +05:30
|
|
|
SRV_UNDO_TABLESPACE_SIZE_IN_PAGES, mtr);
|
|
|
|
if (err) return err;
|
2019-12-04 15:00:57 +02:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return DB_SUCCESS;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
/** Create the temporary file tablespace.
|
|
|
|
@param[in] create_new_db whether we are creating a new database
|
|
|
|
@return DB_SUCCESS or error code. */
|
|
|
|
static
|
|
|
|
dberr_t
|
2016-12-16 16:36:54 +02:00
|
|
|
srv_open_tmp_tablespace(bool create_new_db)
|
2016-08-12 11:17:45 +03:00
|
|
|
{
|
|
|
|
ulint sum_of_new_sizes;
|
|
|
|
|
|
|
|
/* Will try to remove if there is existing file left-over by last
|
|
|
|
unclean shutdown */
|
2016-12-16 16:36:54 +02:00
|
|
|
srv_tmp_space.set_sanity_check_status(true);
|
|
|
|
srv_tmp_space.delete_files();
|
|
|
|
srv_tmp_space.set_ignore_read_only(true);
|
2016-08-12 11:17:45 +03:00
|
|
|
|
|
|
|
bool create_new_temp_space;
|
|
|
|
|
2016-12-16 16:36:54 +02:00
|
|
|
srv_tmp_space.set_space_id(SRV_TMP_SPACE_ID);
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2016-12-16 16:36:54 +02:00
|
|
|
dberr_t err = srv_tmp_space.check_file_spec(
|
|
|
|
&create_new_temp_space, 12 * 1024 * 1024);
|
2016-08-12 11:17:45 +03:00
|
|
|
|
|
|
|
if (err == DB_FAIL) {
|
2018-03-28 09:29:14 +03:00
|
|
|
ib::error() << "The innodb_temporary"
|
|
|
|
" data file must be writable!";
|
2016-08-12 11:17:45 +03:00
|
|
|
err = DB_ERROR;
|
|
|
|
} else if (err != DB_SUCCESS) {
|
2018-03-28 09:29:14 +03:00
|
|
|
ib::error() << "Could not create the shared innodb_temporary.";
|
2016-12-16 16:36:54 +02:00
|
|
|
} else if ((err = srv_tmp_space.open_or_create(
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
true, create_new_db, &sum_of_new_sizes))
|
2016-08-12 11:17:45 +03:00
|
|
|
!= DB_SUCCESS) {
|
2018-03-28 09:29:14 +03:00
|
|
|
ib::error() << "Unable to create the shared innodb_temporary";
|
2020-10-26 15:59:30 +02:00
|
|
|
} else if (fil_system.temp_space->open(true)) {
|
2018-03-28 09:29:14 +03:00
|
|
|
/* Initialize the header page */
|
|
|
|
mtr_t mtr;
|
|
|
|
mtr.start();
|
|
|
|
mtr.set_log_mode(MTR_LOG_NO_REDO);
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
err = fsp_header_init(fil_system.temp_space,
|
|
|
|
srv_tmp_space.get_sum_of_sizes(),
|
|
|
|
&mtr);
|
2018-03-28 09:29:14 +03:00
|
|
|
mtr.commit();
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
if (err == DB_SUCCESS) {
|
|
|
|
err = trx_temp_rseg_create(&mtr);
|
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
} else {
|
2018-03-28 09:29:14 +03:00
|
|
|
/* This file was just opened in the code above! */
|
|
|
|
ib::error() << "The innodb_temporary"
|
|
|
|
" data file cannot be re-opened"
|
|
|
|
" after check_file_spec() succeeded!";
|
|
|
|
err = DB_ERROR;
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
|
|
|
|
|
|
|
return(err);
|
|
|
|
}
|
|
|
|
|
2020-10-26 15:04:24 +02:00
|
|
|
/** Shutdown background threads, except the page cleaner. */
|
|
|
|
static void srv_shutdown_threads()
|
2016-08-12 11:17:45 +03:00
|
|
|
{
|
2017-06-29 11:31:01 +03:00
|
|
|
ut_ad(!srv_undo_sources);
|
2019-10-29 22:37:12 +01:00
|
|
|
srv_master_timer.reset();
|
2021-07-21 15:44:32 +03:00
|
|
|
srv_shutdown_state = SRV_SHUTDOWN_EXIT_THREADS;
|
2019-10-29 22:37:12 +01:00
|
|
|
|
|
|
|
if (purge_sys.enabled()) {
|
|
|
|
srv_purge_shutdown();
|
|
|
|
}
|
|
|
|
|
2020-10-26 15:04:24 +02:00
|
|
|
if (srv_n_fil_crypt_threads) {
|
|
|
|
fil_crypt_set_thread_cnt(0);
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2022-09-26 13:45:53 +03:00
|
|
|
|
|
|
|
/** Shut down background threads that can generate undo log. */
|
|
|
|
static void srv_shutdown_bg_undo_sources()
|
|
|
|
{
|
|
|
|
srv_shutdown_state= SRV_SHUTDOWN_INITIATED;
|
|
|
|
|
|
|
|
if (srv_undo_sources)
|
|
|
|
{
|
|
|
|
ut_ad(!srv_read_only_mode);
|
|
|
|
fts_optimize_shutdown();
|
|
|
|
dict_stats_shutdown();
|
|
|
|
srv_undo_sources= false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
# define srv_init_abort(_db_err) \
|
|
|
|
srv_init_abort_low(create_new_db, __FILE__, __LINE__, _db_err)
|
|
|
|
#else
|
|
|
|
# define srv_init_abort(_db_err) \
|
|
|
|
srv_init_abort_low(create_new_db, _db_err)
|
|
|
|
#endif /* UNIV_DEBUG */
|
|
|
|
|
|
|
|
/** Innobase start-up aborted. Perform cleanup actions.
|
|
|
|
@param[in] create_new_db TRUE if new db is being created
|
|
|
|
@param[in] file File name
|
|
|
|
@param[in] line Line number
|
|
|
|
@param[in] err Reason for aborting InnoDB startup
|
|
|
|
@return DB_SUCCESS or error code. */
|
2017-01-25 15:11:46 +02:00
|
|
|
MY_ATTRIBUTE((warn_unused_result, nonnull))
|
2016-08-12 11:17:45 +03:00
|
|
|
static
|
|
|
|
dberr_t
|
|
|
|
srv_init_abort_low(
|
|
|
|
bool create_new_db,
|
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
const char* file,
|
2017-03-01 08:27:39 +02:00
|
|
|
unsigned line,
|
2016-08-12 11:17:45 +03:00
|
|
|
#endif /* UNIV_DEBUG */
|
|
|
|
dberr_t err)
|
|
|
|
{
|
MDEV-15053 Reduce buf_pool_t::mutex contention
User-visible changes: The INFORMATION_SCHEMA views INNODB_BUFFER_PAGE
and INNODB_BUFFER_PAGE_LRU will report a dummy value FLUSH_TYPE=0
and will no longer report the PAGE_STATE value READY_FOR_USE.
We will remove some fields from buf_page_t and move much code to
member functions of buf_pool_t and buf_page_t, so that the access
rules of data members can be enforced consistently.
Evicting or adding pages in buf_pool.LRU will remain covered by
buf_pool.mutex.
Evicting or adding pages in buf_pool.page_hash will remain
covered by both buf_pool.mutex and the buf_pool.page_hash X-latch.
After this fix, buf_pool.page_hash lookups can entirely
avoid acquiring buf_pool.mutex, only relying on
buf_pool.hash_lock_get() S-latch.
Similarly, buf_flush_check_neighbors() can will rely solely on
buf_pool.mutex, no buf_pool.page_hash latch at all.
The buf_pool.mutex is rather contended in I/O heavy benchmarks,
especially when the workload does not fit in the buffer pool.
The first attempt to alleviate the contention was the
buf_pool_t::mutex split in
commit 4ed7082eefe56b3e97e0edefb3df76dd7ef5e858
which introduced buf_block_t::mutex, which we are now removing.
Later, multiple instances of buf_pool_t were introduced
in commit c18084f71b02ea707c6461353e6cfc15d7553bc6
and recently removed by us in
commit 1a6f708ec594ac0ae2dd30db926ab07b100fa24b (MDEV-15058).
UNIV_BUF_DEBUG: Remove. This option to enable some buffer pool
related debugging in otherwise non-debug builds has not been used
for years. Instead, we have been using UNIV_DEBUG, which is enabled
in CMAKE_BUILD_TYPE=Debug.
buf_block_t::mutex, buf_pool_t::zip_mutex: Remove. We can mainly rely on
std::atomic and the buf_pool.page_hash latches, and in some cases
depend on buf_pool.mutex or buf_pool.flush_list_mutex just like before.
We must always release buf_block_t::lock before invoking
unfix() or io_unfix(), to prevent a glitch where a block that was
added to the buf_pool.free list would apper X-latched. See
commit c5883debd6ef440a037011c11873b396923e93c5 how this glitch
was finally caught in a debug environment.
We move some buf_pool_t::page_hash specific code from the
ha and hash modules to buf_pool, for improved readability.
buf_pool_t::close(): Assert that all blocks are clean, except
on aborted startup or crash-like shutdown.
buf_pool_t::validate(): No longer attempt to validate
n_flush[] against the number of BUF_IO_WRITE fixed blocks,
because buf_page_t::flush_type no longer exists.
buf_pool_t::watch_set(): Replaces buf_pool_watch_set().
Reduce mutex contention by separating the buf_pool.watch[]
allocation and the insert into buf_pool.page_hash.
buf_pool_t::page_hash_lock<bool exclusive>(): Acquire a
buf_pool.page_hash latch.
Replaces and extends buf_page_hash_lock_s_confirm()
and buf_page_hash_lock_x_confirm().
buf_pool_t::READ_AHEAD_PAGES: Renamed from BUF_READ_AHEAD_PAGES.
buf_pool_t::curr_size, old_size, read_ahead_area, n_pend_reads:
Use Atomic_counter.
buf_pool_t::running_out(): Replaces buf_LRU_buf_pool_running_out().
buf_pool_t::LRU_remove(): Remove a block from the LRU list
and return its predecessor. Incorporates buf_LRU_adjust_hp(),
which was removed.
buf_page_get_gen(): Remove a redundant call of fsp_is_system_temporary(),
for mode == BUF_GET_IF_IN_POOL_OR_WATCH, which is only used by
BTR_DELETE_OP (purge), which is never invoked on temporary tables.
buf_free_from_unzip_LRU_list_batch(): Avoid redundant assignments.
buf_LRU_free_from_unzip_LRU_list(): Simplify the loop condition.
buf_LRU_free_page(): Clarify the function comment.
buf_flush_check_neighbor(), buf_flush_check_neighbors():
Rewrite the construction of the page hash range. We will hold
the buf_pool.mutex for up to buf_pool.read_ahead_area (at most 64)
consecutive lookups of buf_pool.page_hash.
buf_flush_page_and_try_neighbors(): Remove.
Merge to its only callers, and remove redundant operations in
buf_flush_LRU_list_batch().
buf_read_ahead_random(), buf_read_ahead_linear(): Rewrite.
Do not acquire buf_pool.mutex, and iterate directly with page_id_t.
ut_2_power_up(): Remove. my_round_up_to_next_power() is inlined
and avoids any loops.
fil_page_get_prev(), fil_page_get_next(), fil_addr_is_null(): Remove.
buf_flush_page(): Add a fil_space_t* parameter. Minimize the
buf_pool.mutex hold time. buf_pool.n_flush[] is no longer updated
atomically with the io_fix, and we will protect most buf_block_t
fields with buf_block_t::lock. The function
buf_flush_write_block_low() is removed and merged here.
buf_page_init_for_read(): Use static linkage. Initialize the newly
allocated block and acquire the exclusive buf_block_t::lock while not
holding any mutex.
IORequest::IORequest(): Remove the body. We only need to invoke
set_punch_hole() in buf_flush_page() and nowhere else.
buf_page_t::flush_type: Remove. Replaced by IORequest::flush_type.
This field is only used during a fil_io() call.
That function already takes IORequest as a parameter, so we had
better introduce for the rarely changing field.
buf_block_t::init(): Replaces buf_page_init().
buf_page_t::init(): Replaces buf_page_init_low().
buf_block_t::initialise(): Initialise many fields, but
keep the buf_page_t::state(). Both buf_pool_t::validate() and
buf_page_optimistic_get() requires that buf_page_t::in_file()
be protected atomically with buf_page_t::in_page_hash
and buf_page_t::in_LRU_list.
buf_page_optimistic_get(): Now that buf_block_t::mutex
no longer exists, we must check buf_page_t::io_fix()
after acquiring the buf_pool.page_hash lock, to detect
whether buf_page_init_for_read() has been initiated.
We will also check the io_fix() before acquiring hash_lock
in order to avoid unnecessary computation.
The field buf_block_t::modify_clock (protected by buf_block_t::lock)
allows buf_page_optimistic_get() to validate the block.
buf_page_t::real_size: Remove. It was only used while flushing
pages of page_compressed tables.
buf_page_encrypt(): Add an output parameter that allows us ot eliminate
buf_page_t::real_size. Replace a condition with debug assertion.
buf_page_should_punch_hole(): Remove.
buf_dblwr_t::add_to_batch(): Replaces buf_dblwr_add_to_batch().
Add the parameter size (to replace buf_page_t::real_size).
buf_dblwr_t::write_single_page(): Replaces buf_dblwr_write_single_page().
Add the parameter size (to replace buf_page_t::real_size).
fil_system_t::detach(): Replaces fil_space_detach().
Ensure that fil_validate() will not be violated even if
fil_system.mutex is released and reacquired.
fil_node_t::complete_io(): Renamed from fil_node_complete_io().
fil_node_t::close_to_free(): Replaces fil_node_close_to_free().
Avoid invoking fil_node_t::close() because fil_system.n_open
has already been decremented in fil_space_t::detach().
BUF_BLOCK_READY_FOR_USE: Remove. Directly use BUF_BLOCK_MEMORY.
BUF_BLOCK_ZIP_DIRTY: Remove. Directly use BUF_BLOCK_ZIP_PAGE,
and distinguish dirty pages by buf_page_t::oldest_modification().
BUF_BLOCK_POOL_WATCH: Remove. Use BUF_BLOCK_NOT_USED instead.
This state was only being used for buf_page_t that are in
buf_pool.watch.
buf_pool_t::watch[]: Remove pointer indirection.
buf_page_t::in_flush_list: Remove. It was set if and only if
buf_page_t::oldest_modification() is nonzero.
buf_page_decrypt_after_read(), buf_corrupt_page_release(),
buf_page_check_corrupt(): Change the const fil_space_t* parameter
to const fil_node_t& so that we can report the correct file name.
buf_page_monitor(): Declare as an ATTRIBUTE_COLD global function.
buf_page_io_complete(): Split to buf_page_read_complete() and
buf_page_write_complete().
buf_dblwr_t::in_use: Remove.
buf_dblwr_t::buf_block_array: Add IORequest::flush_t.
buf_dblwr_sync_datafiles(): Remove. It was a useless wrapper of
os_aio_wait_until_no_pending_writes().
buf_flush_write_complete(): Declare static, not global.
Add the parameter IORequest::flush_t.
buf_flush_freed_page(): Simplify the code.
recv_sys_t::flush_lru: Renamed from flush_type and changed to bool.
fil_read(), fil_write(): Replaced with direct use of fil_io().
fil_buffering_disabled(): Remove. Check srv_file_flush_method directly.
fil_mutex_enter_and_prepare_for_io(): Return the resolved
fil_space_t* to avoid a duplicated lookup in the caller.
fil_report_invalid_page_access(): Clean up the parameters.
fil_io(): Return fil_io_t, which comprises fil_node_t and error code.
Always invoke fil_space_t::acquire_for_io() and let either the
sync=true caller or fil_aio_callback() invoke
fil_space_t::release_for_io().
fil_aio_callback(): Rewrite to replace buf_page_io_complete().
fil_check_pending_operations(): Remove a parameter, and remove some
redundant lookups.
fil_node_close_to_free(): Wait for n_pending==0. Because we no longer
do an extra lookup of the tablespace between fil_io() and the
completion of the operation, we must give fil_node_t::complete_io() a
chance to decrement the counter.
fil_close_tablespace(): Remove unused parameter trx, and document
that this is only invoked during the error handling of IMPORT TABLESPACE.
row_import_discard_changes(): Merged with the only caller,
row_import_cleanup(). Do not lock up the data dictionary while
invoking fil_close_tablespace().
logs_empty_and_mark_files_at_shutdown(): Do not invoke
fil_close_all_files(), to avoid a !needs_flush assertion failure
on fil_node_t::close().
innodb_shutdown(): Invoke os_aio_free() before fil_close_all_files().
fil_close_all_files(): Invoke fil_flush_file_spaces()
to ensure proper durability.
thread_pool::unbind(): Fix a crash that would occur on Windows
after srv_thread_pool->disable_aio() and os_file_close().
This fix was submitted by Vladislav Vaintroub.
Thanks to Matthias Leich and Axel Schwenke for extensive testing,
Vladislav Vaintroub for helpful comments, and Eugene Kosov for a review.
2020-06-05 12:35:46 +03:00
|
|
|
ut_ad(srv_is_being_started);
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
if (create_new_db) {
|
2017-06-08 12:45:08 +03:00
|
|
|
ib::error() << "Database creation was aborted"
|
2016-08-12 11:17:45 +03:00
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
" at " << innobase_basename(file) << "[" << line << "]"
|
|
|
|
#endif /* UNIV_DEBUG */
|
2020-06-04 10:24:10 +03:00
|
|
|
" with error " << err << ". You may need"
|
2016-08-12 11:17:45 +03:00
|
|
|
" to delete the ibdata1 file before trying to start"
|
|
|
|
" up again.";
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
} else if (srv_operation == SRV_OPERATION_NORMAL) {
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::error() << "Plugin initialization aborted"
|
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
" at " << innobase_basename(file) << "[" << line << "]"
|
|
|
|
#endif /* UNIV_DEBUG */
|
2020-06-04 10:24:10 +03:00
|
|
|
" with error " << err;
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
|
|
|
|
2018-01-30 13:39:48 +02:00
|
|
|
srv_shutdown_bg_undo_sources();
|
2020-10-26 15:04:24 +02:00
|
|
|
srv_shutdown_threads();
|
2016-08-12 11:17:45 +03:00
|
|
|
return(err);
|
|
|
|
}
|
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
/** Prepare to delete the redo log file. Flush the dirty pages from all the
|
2016-08-12 11:17:45 +03:00
|
|
|
buffer pools. Flush the redo log buffer to the redo log file.
|
|
|
|
@return lsn upto which data pages have been flushed. */
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
ATTRIBUTE_COLD static lsn_t srv_prepare_to_delete_redo_log_file()
|
2016-08-12 11:17:45 +03:00
|
|
|
{
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
DBUG_ENTER("srv_prepare_to_delete_redo_log_file");
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2023-03-16 13:39:23 +02:00
|
|
|
ut_ad(recv_sys.recovery_on);
|
MDEV-14717: Prevent crash-downgrade to earlier MariaDB 10.2
A crash-downgrade of a RENAME (or TRUNCATE or table-rebuilding
ALTER TABLE or OPTIMIZE TABLE) operation to an earlier 10.2 version
would trigger a debug assertion failure during rollback,
in trx_roll_pop_top_rec_of_trx(). In a non-debug build, the
TRX_UNDO_RENAME_TABLE record would be misinterpreted as an
update_undo log record, and typically the file name would be
interpreted as DB_TRX_ID,DB_ROLL_PTR,PRIMARY KEY. If a matching
record would be found, row_undo_mod() would hit ut_error in
switch (node->rec_type). Typically, ut_a(table2 == NULL) would
fail when opening the table from SQL.
Because of this, we prevent a crash-downgrade to earlier MariaDB 10.2
versions by changing the InnoDB redo log format identifier to the
10.3 identifier, and by introducing a subformat identifier so that
10.2 can continue to refuse crash-downgrade from 10.3 or later.
After a clean shutdown, a downgrade to MariaDB 10.2.13 or later would
still be possible thanks to MDEV-14909. A downgrade to older 10.2
versions is only possible after removing the log files (not recommended).
LOG_HEADER_FORMAT_CURRENT: Change to 103 (originally the 10.3 format).
log_group_t: Add subformat. For 10.2, we will use subformat 1,
and will refuse crash recovery from any other subformat of the
10.3 format, that is, a genuine 10.3 redo log.
recv_find_max_checkpoint(): Allow startup after clean shutdown
from a future LOG_HEADER_FORMAT_10_4 (unencrypted only).
We cannot handle the encrypted 10.4 redo log block format,
which was introduced in MDEV-12041. Allow crash recovery from
the original 10.2 format as well as the new format.
In Mariabackup --backup, do not allow any startup from 10.3 or 10.4
redo logs.
recv_recovery_from_checkpoint_start(): Skip redo log apply for
clean 10.3 redo log, but not for the new 10.2 redo log
(10.3 format, subformat 1).
srv_prepare_to_delete_redo_log_files(): On format or subformat
mismatch, set srv_log_file_size = 0, so that we will display the
correct message.
innobase_start_or_create_for_mysql(): Check for format or subformat
mismatch.
xtrabackup_backup_func(): Remove debug assertions that were made
redundant by the code changes in recv_find_max_checkpoint().
2018-09-07 17:24:31 +03:00
|
|
|
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
/* Clean the buffer pool. */
|
|
|
|
buf_flush_sync();
|
2016-08-12 11:17:45 +03:00
|
|
|
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
DBUG_EXECUTE_IF("innodb_log_abort_1", DBUG_RETURN(0););
|
|
|
|
DBUG_PRINT("ib_log", ("After innodb_log_abort_1"));
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2022-02-10 16:37:12 +02:00
|
|
|
log_sys.latch.wr_lock(SRW_LOCK_CALL);
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
const bool latest_format{log_sys.is_latest()};
|
|
|
|
lsn_t flushed_lsn{log_sys.get_lsn()};
|
|
|
|
|
|
|
|
if (latest_format && !(log_sys.file_size & 4095) &&
|
|
|
|
flushed_lsn != log_sys.next_checkpoint_lsn +
|
|
|
|
(log_sys.is_encrypted()
|
|
|
|
? SIZE_OF_FILE_CHECKPOINT + 8
|
|
|
|
: SIZE_OF_FILE_CHECKPOINT))
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
{
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
fil_names_clear(flushed_lsn);
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
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|
|
flushed_lsn= log_sys.get_lsn();
|
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
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|
|
{
|
|
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|
const char *msg;
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
if (!latest_format)
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
{
|
|
|
|
msg= "Upgrading redo log: ";
|
|
|
|
same_size:
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
ib::info() << msg << ib::bytes_iec(srv_log_file_size)
|
2021-12-03 12:12:14 +11:00
|
|
|
<< "; LSN=" << flushed_lsn;
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
}
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
else if (srv_log_file_size == log_sys.file_size)
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
{
|
|
|
|
msg= srv_encrypt_log
|
|
|
|
? "Encrypting redo log: " : "Removing redo log encryption: ";
|
|
|
|
goto same_size;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
if (srv_encrypt_log == (my_bool)log_sys.is_encrypted())
|
|
|
|
msg= srv_encrypt_log ? "Resizing encrypted" : "Resizing";
|
|
|
|
else
|
|
|
|
msg= srv_encrypt_log
|
|
|
|
? "Encrypting and resizing"
|
|
|
|
: "Removing encryption and resizing";
|
|
|
|
|
2021-12-03 12:12:14 +11:00
|
|
|
ib::info() << msg << " redo log from "
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
<< ib::bytes_iec{log_sys.file_size} << " to "
|
|
|
|
<< ib::bytes_iec{srv_log_file_size}
|
2021-12-03 12:12:14 +11:00
|
|
|
<< "; LSN=" << flushed_lsn;
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
}
|
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2022-02-10 16:37:12 +02:00
|
|
|
log_sys.latch.wr_unlock();
|
2020-06-08 13:14:27 +03:00
|
|
|
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
log_write_up_to(flushed_lsn, false);
|
2016-08-12 11:17:45 +03:00
|
|
|
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
ut_ad(flushed_lsn == log_sys.get_lsn());
|
2023-04-12 13:49:57 +03:00
|
|
|
ut_ad(!os_aio_pending_reads());
|
|
|
|
ut_d(mysql_mutex_lock(&buf_pool.flush_list_mutex));
|
|
|
|
ut_ad(!buf_pool.get_oldest_modification(0));
|
|
|
|
ut_d(mysql_mutex_unlock(&buf_pool.flush_list_mutex));
|
2023-04-24 09:57:58 +03:00
|
|
|
ut_d(os_aio_wait_until_no_pending_writes(false));
|
2016-08-12 11:17:45 +03:00
|
|
|
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
DBUG_RETURN(flushed_lsn);
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
|
|
|
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
/** Upgrade the redo log to the latest format, or change its size
|
|
|
|
or encryption, before starting to write any log records. */
|
|
|
|
ATTRIBUTE_COLD static dberr_t srv_log_rebuild()
|
|
|
|
{
|
|
|
|
/* Prepare to delete the old redo log file */
|
|
|
|
const lsn_t lsn{srv_prepare_to_delete_redo_log_file()};
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("innodb_log_abort_1", return DB_ERROR;);
|
|
|
|
/* Prohibit redo log writes from any other threads until creating a
|
|
|
|
log checkpoint at the end of create_log_file(). */
|
|
|
|
ut_d(recv_no_log_write= true);
|
2023-04-14 17:40:41 +03:00
|
|
|
ut_ad(!os_aio_pending_reads());
|
|
|
|
ut_d(mysql_mutex_lock(&buf_pool.flush_list_mutex));
|
|
|
|
ut_ad(!buf_pool.get_oldest_modification(0));
|
|
|
|
ut_d(mysql_mutex_unlock(&buf_pool.flush_list_mutex));
|
2023-10-19 08:12:16 +03:00
|
|
|
/* os_aio_pending_writes() may hold here if some write_io_callback()
|
|
|
|
did not release the slot yet. However, the page write itself must
|
|
|
|
have completed, because the buf_pool.flush_list is empty. In debug
|
|
|
|
builds, we wait for this to happen, hoping to get a hung process if
|
|
|
|
this assumption does not hold. */
|
|
|
|
ut_d(os_aio_wait_until_no_pending_writes(false));
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
|
|
|
|
/* Close the redo log file, so that we can replace it */
|
|
|
|
log_sys.close_file();
|
|
|
|
|
|
|
|
DBUG_EXECUTE_IF("innodb_log_abort_5", return DB_ERROR;);
|
|
|
|
|
|
|
|
dberr_t err= create_log_file(false, lsn);
|
|
|
|
|
|
|
|
if (err == DB_SUCCESS && log_sys.resize_rename())
|
|
|
|
err = DB_ERROR;
|
|
|
|
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
/** Rebuild the redo log if needed. */
|
|
|
|
static dberr_t srv_log_rebuild_if_needed()
|
|
|
|
{
|
|
|
|
if (srv_force_recovery == SRV_FORCE_NO_LOG_REDO)
|
|
|
|
/* Completely ignore the redo log. */
|
|
|
|
return DB_SUCCESS;
|
|
|
|
if (srv_read_only_mode)
|
|
|
|
/* Leave the redo log alone. */
|
|
|
|
return DB_SUCCESS;
|
|
|
|
|
|
|
|
if (log_sys.file_size == srv_log_file_size &&
|
|
|
|
log_sys.format ==
|
|
|
|
(srv_encrypt_log ? log_t::FORMAT_ENC_10_8 : log_t::FORMAT_10_8))
|
|
|
|
{
|
|
|
|
/* No need to add or remove encryption, upgrade, or resize. */
|
|
|
|
delete_log_files();
|
|
|
|
return DB_SUCCESS;
|
|
|
|
}
|
|
|
|
|
|
|
|
return srv_log_rebuild();
|
|
|
|
}
|
|
|
|
|
|
|
|
ATTRIBUTE_COLD static dberr_t ibuf_log_rebuild_if_needed()
|
|
|
|
{
|
|
|
|
mysql_mutex_lock(&recv_sys.mutex);
|
|
|
|
recv_sys.apply(true);
|
|
|
|
mysql_mutex_unlock(&recv_sys.mutex);
|
|
|
|
|
|
|
|
if (recv_sys.is_corrupt_log() || recv_sys.is_corrupt_fs())
|
|
|
|
return DB_CORRUPTION;
|
|
|
|
|
2023-07-05 12:37:05 +03:00
|
|
|
dberr_t err= srv_log_rebuild_if_needed();
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
recv_sys.debug_free();
|
2023-07-05 12:37:05 +03:00
|
|
|
return err;
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
}
|
|
|
|
|
2021-03-17 10:03:06 +03:00
|
|
|
static tpool::task_group rollback_all_recovered_group(1);
|
|
|
|
static tpool::task rollback_all_recovered_task(trx_rollback_all_recovered,
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
nullptr,
|
|
|
|
&rollback_all_recovered_group);
|
2021-03-17 10:03:06 +03:00
|
|
|
|
2018-04-29 09:41:42 +03:00
|
|
|
/** Start InnoDB.
|
|
|
|
@param[in] create_new_db whether to create a new database
|
2016-08-12 11:17:45 +03:00
|
|
|
@return DB_SUCCESS or error code */
|
2018-04-29 09:41:42 +03:00
|
|
|
dberr_t srv_start(bool create_new_db)
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
2017-01-31 19:43:03 +02:00
|
|
|
dberr_t err = DB_SUCCESS;
|
2014-02-26 19:11:54 +01:00
|
|
|
mtr_t mtr;
|
|
|
|
|
2023-03-31 21:32:41 +02:00
|
|
|
ut_ad(srv_operation <= SRV_OPERATION_RESTORE_EXPORT
|
2017-10-10 10:28:54 +03:00
|
|
|
|| srv_operation == SRV_OPERATION_RESTORE
|
|
|
|
|| srv_operation == SRV_OPERATION_RESTORE_EXPORT);
|
MDEV-12548 Initial implementation of Mariabackup for MariaDB 10.2
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
2017-06-30 10:49:37 +03:00
|
|
|
|
2021-06-21 12:34:07 +03:00
|
|
|
if (srv_force_recovery) {
|
|
|
|
ib::info() << "!!! innodb_force_recovery is set to "
|
|
|
|
<< srv_force_recovery << " !!!";
|
|
|
|
}
|
|
|
|
|
2017-02-01 16:03:57 +05:30
|
|
|
if (srv_force_recovery == SRV_FORCE_NO_LOG_REDO) {
|
|
|
|
srv_read_only_mode = true;
|
|
|
|
}
|
|
|
|
|
2015-10-09 17:21:46 +02:00
|
|
|
high_level_read_only = srv_read_only_mode
|
MDEV-25683 Atomic DDL: With innodb_force_recovery=3 InnoDB: Trying to load index but the index tree has been freed
The purpose of the parameter innodb_force_recovery is to allow some
data to be dumped from a corrupted database. Its values used to be
as follows:
innodb_force_recovery=0: normal (default)
innodb_force_recovery=1: ignore (skip log for) corrupted pages or
missing data files when applying the redo log
innodb_force_recovery=2: additionally, disable background tasks
(such as the purge of committed undo logs)
innodb_force_recovery=3: additionally, disable the rollback of
recovered incomplete (not committed or XA PREPARE) transactions
innodb_force_recovery=4: same as 3 (since MDEV-19514 in MariaDB 10.5)
innodb_force_recovery=5: additionally, do not process any undo log,
disallow any writes, and force READ UNCOMMITTED isolation level
innodb_force_recovery=6: additionally, pretend that ib_logfile0 does
not exist (prevent any recovery). Never use this!
The bad thing that happens with innodb_force_recovery=3 and
innodb_force_recovery=4 is that also the rollback of any recovered
DDL transaction will be skipped. This would break the DDL log recovery
that was introduced in MDEV-17567.
For one data directory sample, the DDL log recovery would hangs due to
a conflict on the InnoDB SYS_TABLES table, because the lock holder
transaction was not rolled back due to innodb_force_recovery=3.
Fix: Make innodb_force_recovery=3 skip the DML transaction rollback only,
and make innodb_force_recovery=4 (renamed to SRV_FORCE_NO_DDL_UNDO)
behave like innodb_force_recovery=3 used to (skip the rollback of all
recovered transactions, both DML and DDL).
Startup with innodb_force_recovery=4 will be unaffected by this change.
(There may be hangs, possibly preceded by messages about failing to
load an index.)
Side note: With innodb_force_recovery=5, any DDL log for InnoDB tables
will be essentially ignored by InnoDB, but the server will start up.
2021-10-29 10:20:58 +03:00
|
|
|
|| srv_force_recovery >= SRV_FORCE_NO_UNDO_LOG_SCAN
|
2018-03-29 12:55:24 +03:00
|
|
|
|| srv_sys_space.created_new_raw();
|
2014-02-26 19:23:04 +01:00
|
|
|
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
srv_started_redo = false;
|
2017-02-10 17:01:45 +01:00
|
|
|
|
2017-01-26 14:05:00 +02:00
|
|
|
compile_time_assert(sizeof(ulint) == sizeof(void*));
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
#ifdef UNIV_DEBUG
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "!!!!!!!! UNIV_DEBUG switched on !!!!!!!!!";
|
2014-02-26 19:11:54 +01:00
|
|
|
#endif
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Compressed tables use zlib " ZLIB_VERSION
|
2014-02-26 19:11:54 +01:00
|
|
|
#ifdef UNIV_ZIP_DEBUG
|
|
|
|
" with validation"
|
|
|
|
#endif /* UNIV_ZIP_DEBUG */
|
2016-08-12 11:17:45 +03:00
|
|
|
;
|
2014-02-26 19:11:54 +01:00
|
|
|
#ifdef UNIV_ZIP_COPY
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "and extra copying";
|
2014-02-26 19:11:54 +01:00
|
|
|
#endif /* UNIV_ZIP_COPY */
|
|
|
|
|
|
|
|
/* Since InnoDB does not currently clean up all its internal data
|
|
|
|
structures in MySQL Embedded Server Library server_end(), we
|
|
|
|
print an error message if someone tries to start up InnoDB a
|
2016-08-12 11:17:45 +03:00
|
|
|
second time during the process lifetime. */
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
if (srv_start_has_been_called) {
|
|
|
|
ib::error() << "Startup called second time"
|
|
|
|
" during the process lifetime."
|
2021-03-18 13:17:30 +05:30
|
|
|
" In the MariaDB Embedded Server Library"
|
2016-08-12 11:17:45 +03:00
|
|
|
" you cannot call server_init() more than"
|
|
|
|
" once during the process lifetime.";
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2017-04-25 09:26:01 +03:00
|
|
|
srv_start_has_been_called = true;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
srv_is_being_started = true;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
/* Register performance schema stages before any real work has been
|
|
|
|
started which may need to be instrumented. */
|
MDEV-21907: InnoDB: Enable -Wconversion on clang and GCC
The -Wconversion in GCC seems to be stricter than in clang.
GCC at least since version 4.4.7 issues truncation warnings for
assignments to bitfields, while clang 10 appears to only issue
warnings when the sizes in bytes rounded to the nearest integer
powers of 2 are different.
Before GCC 10.0.0, -Wconversion required more casts and would not
allow some operations, such as x<<=1 or x+=1 on a data type that
is narrower than int.
GCC 5 (but not GCC 4, GCC 6, or any later version) is complaining
about x|=y even when x and y are compatible types that are narrower
than int. Hence, we must rewrite some x|=y as
x=static_cast<byte>(x|y) or similar, or we must disable -Wconversion.
In GCC 6 and later, the warning for assigning wider to bitfields
that are narrower than 8, 16, or 32 bits can be suppressed by
applying a bitwise & with the exact bitmask of the bitfield.
For older GCC, we must disable -Wconversion for GCC 4 or 5 in such
cases.
The bitwise negation operator appears to promote short integers
to a wider type, and hence we must add explicit truncation casts
around them. Microsoft Visual C does not allow a static_cast to
truncate a constant, such as static_cast<byte>(1) truncating int.
Hence, we will use the constructor-style cast byte(~1) for such cases.
This has been tested at least with GCC 4.8.5, 5.4.0, 7.4.0, 9.2.1, 10.0.0,
clang 9.0.1, 10.0.0, and MSVC 14.22.27905 (Microsoft Visual Studio 2019)
on 64-bit and 32-bit targets (IA-32, AMD64, POWER 8, POWER 9, ARMv8).
2020-03-12 19:46:41 +02:00
|
|
|
mysql_stage_register("innodb", srv_stages,
|
|
|
|
static_cast<int>(UT_ARR_SIZE(srv_stages)));
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-12-04 18:07:25 +02:00
|
|
|
srv_max_n_threads =
|
|
|
|
1 /* dict_stats_thread */
|
|
|
|
+ 1 /* fts_optimize_thread */
|
|
|
|
+ 128 /* safety margin */
|
|
|
|
+ max_connections;
|
2014-02-26 19:23:04 +01:00
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
srv_boot();
|
|
|
|
|
2020-09-17 16:07:37 +02:00
|
|
|
ib::info() << my_crc32c_implementation();
|
2016-12-01 12:35:59 +11:00
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
if (!srv_read_only_mode) {
|
2020-12-04 19:02:58 +02:00
|
|
|
mysql_mutex_init(srv_monitor_file_mutex_key,
|
|
|
|
&srv_monitor_file_mutex, nullptr);
|
|
|
|
mysql_mutex_init(srv_misc_tmpfile_mutex_key,
|
|
|
|
&srv_misc_tmpfile_mutex, nullptr);
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-12-04 19:02:58 +02:00
|
|
|
if (!srv_read_only_mode) {
|
2014-02-26 19:11:54 +01:00
|
|
|
if (srv_innodb_status) {
|
|
|
|
|
|
|
|
srv_monitor_file_name = static_cast<char*>(
|
2016-08-12 11:17:45 +03:00
|
|
|
ut_malloc_nokey(
|
2014-02-26 19:11:54 +01:00
|
|
|
strlen(fil_path_to_mysql_datadir)
|
|
|
|
+ 20 + sizeof "/innodb_status."));
|
|
|
|
|
2016-09-06 09:43:16 +03:00
|
|
|
sprintf(srv_monitor_file_name,
|
|
|
|
"%s/innodb_status." ULINTPF,
|
2014-02-26 19:11:54 +01:00
|
|
|
fil_path_to_mysql_datadir,
|
2020-09-03 16:40:28 +03:00
|
|
|
static_cast<ulint>
|
|
|
|
(IF_WIN(GetCurrentProcessId(), getpid())));
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2019-05-23 12:55:03 +04:00
|
|
|
srv_monitor_file = my_fopen(srv_monitor_file_name,
|
|
|
|
O_RDWR|O_TRUNC|O_CREAT,
|
|
|
|
MYF(MY_WME));
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
if (!srv_monitor_file) {
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::error() << "Unable to create "
|
|
|
|
<< srv_monitor_file_name << ": "
|
|
|
|
<< strerror(errno);
|
2017-03-08 22:36:10 +02:00
|
|
|
if (err == DB_SUCCESS) {
|
|
|
|
err = DB_ERROR;
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
} else {
|
2016-08-12 11:17:45 +03:00
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
srv_monitor_file_name = NULL;
|
2018-03-15 13:47:28 +11:00
|
|
|
srv_monitor_file = os_file_create_tmpfile();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2017-03-08 22:36:10 +02:00
|
|
|
if (!srv_monitor_file && err == DB_SUCCESS) {
|
|
|
|
err = DB_ERROR;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2018-03-15 13:47:28 +11:00
|
|
|
srv_misc_tmpfile = os_file_create_tmpfile();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2017-03-08 22:36:10 +02:00
|
|
|
if (!srv_misc_tmpfile && err == DB_SUCCESS) {
|
|
|
|
err = DB_ERROR;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2017-03-08 22:36:10 +02:00
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return(srv_init_abort(err));
|
|
|
|
}
|
|
|
|
|
2020-12-14 15:27:03 +02:00
|
|
|
if (os_aio_init()) {
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::error() << "Cannot initialize AIO sub-system";
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
return(srv_init_abort(DB_ERROR));
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2020-12-14 15:27:03 +02:00
|
|
|
#ifdef LINUX_NATIVE_AIO
|
|
|
|
if (srv_use_native_aio) {
|
|
|
|
ib::info() << "Using Linux native AIO";
|
|
|
|
}
|
|
|
|
#endif
|
2021-03-15 11:30:17 +02:00
|
|
|
#ifdef HAVE_URING
|
|
|
|
if (srv_use_native_aio) {
|
|
|
|
ib::info() << "Using liburing";
|
|
|
|
}
|
|
|
|
#endif
|
2020-12-14 15:27:03 +02:00
|
|
|
|
2018-03-28 09:00:06 +03:00
|
|
|
fil_system.create(srv_file_per_table ? 50000 : 5000);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Initializing buffer pool, total size = "
|
2021-12-03 12:12:14 +11:00
|
|
|
<< ib::bytes_iec{srv_buf_pool_size}
|
|
|
|
<< ", chunk size = " << ib::bytes_iec{srv_buf_pool_chunk_unit};
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-03-18 21:48:00 +02:00
|
|
|
if (buf_pool.create()) {
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::error() << "Cannot allocate memory for the buffer pool";
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
return(srv_init_abort(DB_ERROR));
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Completed initialization of buffer pool";
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
/* We have observed deadlocks with a 5MB buffer pool but
|
|
|
|
the actual lower limit could very well be a little higher. */
|
|
|
|
|
|
|
|
if (srv_buf_pool_size <= 5 * 1024 * 1024) {
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Small buffer pool size ("
|
2021-12-03 12:12:14 +11:00
|
|
|
<< ib::bytes_iec{srv_buf_pool_size}
|
|
|
|
<< "), the flst_validate() debug function can cause a"
|
2016-08-12 11:17:45 +03:00
|
|
|
<< " deadlock if the buffer pool fills up.";
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
#endif /* UNIV_DEBUG */
|
|
|
|
|
2023-10-11 12:22:33 +03:00
|
|
|
if (!log_sys.create()) {
|
|
|
|
return srv_init_abort(DB_ERROR);
|
|
|
|
}
|
|
|
|
|
2019-05-24 16:19:38 +03:00
|
|
|
recv_sys.create();
|
2018-02-22 20:46:42 +04:00
|
|
|
lock_sys.create(srv_lock_table_size);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-03-29 14:53:51 +03:00
|
|
|
srv_startup_is_before_trx_rollback_phase = true;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-12-05 21:04:30 +02:00
|
|
|
if (!srv_read_only_mode) {
|
|
|
|
buf_flush_page_cleaner_init();
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
ut_ad(buf_page_cleaner_is_active);
|
2016-12-05 21:04:30 +02:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
/* Check if undo tablespaces and redo log files exist before creating
|
|
|
|
a new system tablespace */
|
|
|
|
if (create_new_db) {
|
|
|
|
err = srv_check_undo_redo_logs_exists();
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return(srv_init_abort(DB_ERROR));
|
|
|
|
}
|
2019-05-24 16:19:38 +03:00
|
|
|
recv_sys.debug_free();
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
/* Open or create the data files. */
|
|
|
|
ulint sum_of_new_sizes;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
err = srv_sys_space.open_or_create(
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
false, create_new_db, &sum_of_new_sizes);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
switch (err) {
|
|
|
|
case DB_SUCCESS:
|
|
|
|
break;
|
|
|
|
case DB_CANNOT_OPEN_FILE:
|
|
|
|
ib::error()
|
|
|
|
<< "Could not open or create the system tablespace. If"
|
|
|
|
" you tried to add new data files to the system"
|
|
|
|
" tablespace, and it failed here, you should now"
|
|
|
|
" edit innodb_data_file_path in my.cnf back to what"
|
|
|
|
" it was, and remove the new ibdata files InnoDB"
|
|
|
|
" created in this failed attempt. InnoDB only wrote"
|
|
|
|
" those files full of zeros, but did not yet use"
|
|
|
|
" them in any way. But be careful: do not remove"
|
|
|
|
" old data files which contain your precious data!";
|
|
|
|
/* fall through */
|
|
|
|
default:
|
|
|
|
/* Other errors might come from Datafile::validate_first_page() */
|
|
|
|
return(srv_init_abort(err));
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2019-07-01 18:50:44 +05:30
|
|
|
if (innodb_encrypt_temporary_tables && !log_crypt_init()) {
|
2019-06-27 16:23:03 +05:30
|
|
|
return srv_init_abort(DB_ERROR);
|
|
|
|
}
|
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
if (create_new_db) {
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
lsn_t flushed_lsn = log_sys.init_lsn();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-02-14 19:49:54 +02:00
|
|
|
err = create_log_file(true, flushed_lsn);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
if (err != DB_SUCCESS) {
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
for (const Datafile &file: srv_sys_space) {
|
2021-12-15 14:17:55 +02:00
|
|
|
os_file_delete(innodb_data_file_key,
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
file.filepath());
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
2020-01-12 02:05:28 +07:00
|
|
|
return srv_init_abort(err);
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
2022-10-24 20:46:43 +05:30
|
|
|
|
|
|
|
srv_undo_space_id_start= 1;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2020-01-12 02:05:28 +07:00
|
|
|
/* Open log file and data files in the systemtablespace: we keep
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
them open until database shutdown */
|
2018-03-28 09:29:14 +03:00
|
|
|
ut_d(fil_system.sys_space->recv_size = srv_sys_space_size_debug);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
if (fil_system.sys_space->open(create_new_db)) {
|
|
|
|
mtr_t mtr;
|
|
|
|
mtr.start();
|
|
|
|
err= srv_undo_tablespaces_init(create_new_db, &mtr);
|
|
|
|
mtr.commit();
|
|
|
|
}
|
|
|
|
else {
|
|
|
|
err= DB_ERROR;
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
/* If the force recovery is set very high then we carry on regardless
|
|
|
|
of all errors. Basically this is fingers crossed mode. */
|
|
|
|
|
|
|
|
if (err != DB_SUCCESS
|
|
|
|
&& srv_force_recovery < SRV_FORCE_NO_UNDO_LOG_SCAN) {
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
return(srv_init_abort(err));
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Initialize objects used by dict stats gathering thread, which
|
|
|
|
can also be used by recovery if it tries to drop some table */
|
|
|
|
if (!srv_read_only_mode) {
|
2019-10-29 22:37:12 +01:00
|
|
|
dict_stats_init();
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2017-12-22 16:15:41 +02:00
|
|
|
trx_sys.create();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
if (create_new_db) {
|
2019-11-13 18:14:44 +01:00
|
|
|
ut_ad(!srv_read_only_mode);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
mtr.start();
|
2018-03-22 14:17:43 +02:00
|
|
|
ut_ad(fil_system.sys_space->id == 0);
|
2017-06-06 14:59:42 +03:00
|
|
|
compile_time_assert(TRX_SYS_SPACE == 0);
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
err = fsp_header_init(fil_system.sys_space,
|
|
|
|
uint32_t(sum_of_new_sizes), &mtr);
|
|
|
|
/* Allocate dummy change buffer pages for backward
|
|
|
|
compatibility and to prevent a downgrade. */
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
} else if (buf_block_t *b =
|
|
|
|
fseg_create(fil_system.sys_space, PAGE_DATA, &mtr,
|
|
|
|
&err)) {
|
|
|
|
ut_ad(b->page.id()
|
|
|
|
== page_id_t(0, FSP_IBUF_HEADER_PAGE_NO));
|
|
|
|
b = fseg_alloc_free_page_general(
|
|
|
|
b->page.frame + PAGE_DATA,
|
|
|
|
FSP_IBUF_TREE_ROOT_PAGE_NO, FSP_UP, false,
|
|
|
|
&mtr, &mtr, &err);
|
|
|
|
if (b) {
|
|
|
|
ut_ad(b->page.id() == page_id_t
|
|
|
|
(0, FSP_IBUF_TREE_ROOT_PAGE_NO));
|
|
|
|
mtr.set_modified(*b);
|
|
|
|
fsp_init_file_page(fil_system.sys_space, b,
|
|
|
|
&mtr);
|
|
|
|
} else {
|
|
|
|
ut_ad(err != DB_SUCCESS);
|
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
/* To maintain backward compatibility we create only
|
|
|
|
the first rollback segment before the double write buffer.
|
|
|
|
All the remaining rollback segments will be created later,
|
|
|
|
after the double write buffer has been created. */
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
if (err == DB_SUCCESS) {
|
|
|
|
err = trx_sys_create_sys_pages(&mtr);
|
|
|
|
}
|
|
|
|
mtr.commit();
|
2021-06-21 12:34:07 +03:00
|
|
|
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return(srv_init_abort(err));
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
err = dict_create();
|
|
|
|
|
|
|
|
if (err != DB_SUCCESS) {
|
2016-08-12 11:17:45 +03:00
|
|
|
return(srv_init_abort(err));
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2020-02-12 14:45:21 +02:00
|
|
|
buf_flush_sync();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-27812 Allow SET GLOBAL innodb_log_file_size
We support online log resizing by replicating the current ib_logfile0
to a new file ib_logfile101, which will eventually replace the
ib_logfile0 on the first applicable log checkpoint.
Unless the log is located in a persistent memory file system (PMEM),
an attempt to SET GLOBAL innodb_log_file_size to less than
innodb_log_buffer_size will be refused. (With PMEM, a.k.a. mmap()
based log, that parameter has no meaning.)
Should the server be killed while the log was being resized,
both files ib_logfile0 and ib_logfile101 may exist on startup,
and since commit 3b06415cb8dfc2b10d9604950f6ed945bc016425
the extra file ib_logfile101 will be removed.
We will initiate checkpoint flushing by invoking buf_flush_ahead(),
to let buf_flush_page_cleaner() write out pages until the
buf_flush_async_lsn target has been reached.
On a log checkpoint, if the new checkpoint LSN is not older than
log_sys.resize_lsn (the start LSN of the ib_logfile101),
we can switch files and complete the log resizing. Else, we will
attempt to switch files on the next checkpoint.
Log resizing can be aborted by killing the connection that is
executing the SET GLOBAL statement.
If the ib_logfile101 wraps around to the beginning, we must
advance the log_sys.resize_lsn. In the resized log file,
the sequence bit will always be written as 1 (no wrap-around).
The log will be duplicated in log_t::resize_write(), invoked by
mtr_t::finish_write().
When the log is being written via system calls (not PMEM), the initial
log_sys.resize_lsn is the current log_sys.first_lsn, plus an integer
multiple of log_sys.block_size, corresponding to the LSN at the start
of the block that was written by log_sys.write_lsn. The log_sys.resize_buf
will be of the same size as the log_sys.buf. During resizing, the
contents of log_sys.buf and log_sys.resize_buf will be identical,
except that the sequence bit of each mini-transaction will always be 1 in
log_sys.resize_buf. If resizing is in progress, log_t::write_buf()
will write log_sys.resize_buf to log_sys.resize_log (ib_logfile101).
If the file would wrap around, the buffer will be written to
log_sys.START_OFFSET and the log_sys.resize_lsn advanced accordingly.
When using mmap() on /dev/shm or a PMEM mount -o dax file system,
the initial log_sys.resize_lsn will be the log_sys.lsn at the time
the resizing is initiated. If the log file wraps around during resizing,
then the log_sys.resize_lsn will be advanced by
(log_sys.resize_target - log_sys.START_OFFSET).
log_t::resize_start(), log_t::resize_abort(), log_t::write_checkpoint():
Unless the log is mmap() based, acquire flush_lock and write_lock.
In any case, acquire exclusive log_sys.latch to prevent race conditions.
log_t::resize_rename(): Renamed from log_t::rename_resized(),
and moved some code to the previous sole caller srv_start().
Thanks to Vladislav Vaintroub for helpful review comments
and to Matthias Leich for testing this, in particular, testing
crash recovery, multiple concurrent SET GLOBAL innodb_log_file_size
and frequently killed connections.
2022-03-02 16:53:04 +02:00
|
|
|
ut_ad(!srv_log_file_created);
|
|
|
|
ut_d(srv_log_file_created= true);
|
|
|
|
|
|
|
|
if (log_sys.resize_rename()) {
|
2022-02-14 19:49:54 +02:00
|
|
|
return(srv_init_abort(DB_ERROR));
|
2016-09-06 09:43:16 +03:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
} else {
|
MDEV-23855: Improve InnoDB log checkpoint performance
After MDEV-15053, MDEV-22871, MDEV-23399 shifted the scalability
bottleneck, log checkpoints became a new bottleneck.
If innodb_io_capacity is set low or innodb_max_dirty_pct_lwm is
set high and the workload fits in the buffer pool, the page cleaner
thread will perform very little flushing. When we reach the capacity
of the circular redo log file ib_logfile0 and must initiate a checkpoint,
some 'furious flushing' will be necessary. (If innodb_flush_sync=OFF,
then flushing would continue at the innodb_io_capacity rate, and
writers would be throttled.)
We have the best chance of advancing the checkpoint LSN immediately
after a page flush batch has been completed. Hence, it is best to
perform checkpoints after every batch in the page cleaner thread,
attempting to run once per second.
By initiating high-priority flushing in the page cleaner as early
as possible, we aim to make the throughput more stable.
The function buf_flush_wait_flushed() used to sleep for 10ms, hoping
that the page cleaner thread would do something during that time.
The observed end result was that a large number of threads that call
log_free_check() would end up sleeping while nothing useful is happening.
We will revise the design so that in the default innodb_flush_sync=ON
mode, buf_flush_wait_flushed() will wake up the page cleaner thread
to perform the necessary flushing, and it will wait for a signal from
the page cleaner thread.
If innodb_io_capacity is set to a low value (causing the page cleaner to
throttle its work), a write workload would initially perform well, until
the capacity of the circular ib_logfile0 is reached and log_free_check()
will trigger checkpoints. At that point, the extra waiting in
buf_flush_wait_flushed() will start reducing throughput.
The page cleaner thread will also initiate log checkpoints after each
buf_flush_lists() call, because that is the best point of time for
the checkpoint LSN to advance by the maximum amount.
Even in 'furious flushing' mode we invoke buf_flush_lists() with
innodb_io_capacity_max pages at a time, and at the start of each
batch (in the log_flush() callback function that runs in a separate
task) we will invoke os_aio_wait_until_no_pending_writes(). This
tweak allows the checkpoint to advance in smaller steps and
significantly reduces the maximum latency. On an Intel Optane 960
NVMe SSD on Linux, it reduced from 4.6 seconds to 74 milliseconds.
On Microsoft Windows with a slower SSD, it reduced from more than
180 seconds to 0.6 seconds.
We will make innodb_adaptive_flushing=OFF simply flush innodb_io_capacity
per second whenever the dirty proportion of buffer pool pages exceeds
innodb_max_dirty_pages_pct_lwm. For innodb_adaptive_flushing=ON we try
to make page_cleaner_flush_pages_recommendation() more consistent and
predictable: if we are below innodb_adaptive_flushing_lwm, let us flush
pages according to the return value of af_get_pct_for_dirty().
innodb_max_dirty_pages_pct_lwm: Revert the change of the default value
that was made in MDEV-23399. The value innodb_max_dirty_pages_pct_lwm=0
guarantees that a shutdown of an idle server will be fast. Users might
be surprised if normal shutdown suddenly became slower when upgrading
within a GA release series.
innodb_checkpoint_usec: Remove. The master task will no longer perform
periodic log checkpoints. It is the duty of the page cleaner thread.
log_sys.max_modified_age: Remove. The current span of the
buf_pool.flush_list expressed in LSN only matters for adaptive
flushing (outside the 'furious flushing' condition).
For the correctness of checkpoints, the only thing that matters is
the checkpoint age (log_sys.lsn - log_sys.last_checkpoint_lsn).
This run-time constant was also reported as log_max_modified_age_sync.
log_sys.max_checkpoint_age_async: Remove. This does not serve any
purpose, because the checkpoints will now be triggered by the page
cleaner thread. We will retain the log_sys.max_checkpoint_age limit
for engaging 'furious flushing'.
page_cleaner.slot: Remove. It turns out that
page_cleaner_slot.flush_list_time was duplicating
page_cleaner.slot.flush_time and page_cleaner.slot.flush_list_pass
was duplicating page_cleaner.flush_pass.
Likewise, there were some redundant monitor counters, because the
page cleaner thread no longer performs any buf_pool.LRU flushing, and
because there only is one buf_flush_page_cleaner thread.
buf_flush_sync_lsn: Protect writes by buf_pool.flush_list_mutex.
buf_pool_t::get_oldest_modification(): Add a parameter to specify the
return value when no persistent data pages are dirty. Require the
caller to hold buf_pool.flush_list_mutex.
log_buf_pool_get_oldest_modification(): Take the fall-back LSN
as a parameter. All callers will also invoke log_sys.get_lsn().
log_preflush_pool_modified_pages(): Replaced with buf_flush_wait_flushed().
buf_flush_wait_flushed(): Implement two limits. If not enough buffer pool
has been flushed, signal the page cleaner (unless innodb_flush_sync=OFF)
and wait for the page cleaner to complete. If the page cleaner
thread is not running (which can be the case durign shutdown),
initiate the flush and wait for it directly.
buf_flush_ahead(): If innodb_flush_sync=ON (the default),
submit a new buf_flush_sync_lsn target for the page cleaner
but do not wait for the flushing to finish.
log_get_capacity(), log_get_max_modified_age_async(): Remove, to make
it easier to see that af_get_pct_for_lsn() is not acquiring any mutexes.
page_cleaner_flush_pages_recommendation(): Protect all access to
buf_pool.flush_list with buf_pool.flush_list_mutex. Previously there
were some race conditions in the calculation.
buf_flush_sync_for_checkpoint(): New function to process
buf_flush_sync_lsn in the page cleaner thread. At the end of
each batch, we try to wake up any blocked buf_flush_wait_flushed().
If everything up to buf_flush_sync_lsn has been flushed, we will
reset buf_flush_sync_lsn=0. The page cleaner thread will keep
'furious flushing' until the limit is reached. Any threads that
are waiting in buf_flush_wait_flushed() will be able to resume
as soon as their own limit has been satisfied.
buf_flush_page_cleaner: Prioritize buf_flush_sync_lsn and do not
sleep as long as it is set. Do not update any page_cleaner statistics
for this special mode of operation. In the normal mode
(buf_flush_sync_lsn is not set for innodb_flush_sync=ON),
try to wake up once per second. No longer check whether
srv_inc_activity_count() has been called. After each batch,
try to perform a log checkpoint, because the best chances for
the checkpoint LSN to advance by the maximum amount are upon
completing a flushing batch.
log_t: Move buf_free, max_buf_free possibly to the same cache line
with log_sys.mutex.
log_margin_checkpoint_age(): Simplify the logic, and replace
a 0.1-second sleep with a call to buf_flush_wait_flushed() to
initiate flushing. Moved to the same compilation unit
with the only caller.
log_close(): Clean up the calculations. (Should be no functional
change.) Return whether flush-ahead is needed. Moved to the same
compilation unit with the only caller.
mtr_t::finish_write(): Return whether flush-ahead is needed.
mtr_t::commit(): Invoke buf_flush_ahead() when needed. Let us avoid
external calls in mtr_t::commit() and make the logic easier to follow
by having related code in a single compilation unit. Also, we will
invoke srv_stats.log_write_requests.inc() only once per
mini-transaction commit, while not holding mutexes.
log_checkpoint_margin(): Only care about log_sys.max_checkpoint_age.
Upon reaching log_sys.max_checkpoint_age where we must wait to prevent
the log from getting corrupted, let us wait for at most 1MiB of LSN
at a time, before rechecking the condition. This should allow writers
to proceed even if the redo log capacity has been reached and
'furious flushing' is in progress. We no longer care about
log_sys.max_modified_age_sync or log_sys.max_modified_age_async.
The log_sys.max_modified_age_sync could be a relic from the time when
there was a srv_master_thread that wrote dirty pages to data files.
Also, we no longer have any log_sys.max_checkpoint_age_async limit,
because log checkpoints will now be triggered by the page cleaner
thread upon completing buf_flush_lists().
log_set_capacity(): Simplify the calculations of the limit
(no functional change).
log_checkpoint_low(): Split from log_checkpoint(). Moved to the
same compilation unit with the caller.
log_make_checkpoint(): Only wait for everything to be flushed until
the current LSN.
create_log_file(): After checkpoint, invoke log_write_up_to()
to ensure that the FILE_CHECKPOINT record has been written.
This avoids ut_ad(!srv_log_file_created) in create_log_file_rename().
srv_start(): Do not call recv_recovery_from_checkpoint_start()
if the log has just been created. Set fil_system.space_id_reuse_warned
before dict_boot() has been executed, and clear it after recovery
has finished.
dict_boot(): Initialize fil_system.max_assigned_id.
srv_check_activity(): Remove. The activity count is counting transaction
commits and therefore mostly interesting for the purge of history.
BtrBulk::insert(): Do not explicitly wake up the page cleaner,
but do invoke srv_inc_activity_count(), because that counter is
still being used in buf_load_throttle_if_needed() for some
heuristics. (It might be cleaner to execute buf_load() in the
page cleaner thread!)
Reviewed by: Vladislav Vaintroub
2020-10-26 16:35:47 +02:00
|
|
|
/* Suppress warnings in fil_space_t::create() for files
|
|
|
|
that are being read before dict_boot() has recovered
|
|
|
|
DICT_HDR_MAX_SPACE_ID. */
|
|
|
|
fil_system.space_id_reuse_warned = true;
|
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
/* We always try to do a recovery, even if the database had
|
|
|
|
been shut down normally: this is the normal startup path */
|
|
|
|
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
err = recv_recovery_from_checkpoint_start();
|
2020-01-12 02:05:28 +07:00
|
|
|
recv_sys.close_files();
|
|
|
|
|
2019-05-24 16:19:38 +03:00
|
|
|
recv_sys.dblwr.pages.clear();
|
2016-08-12 11:17:45 +03:00
|
|
|
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
bool must_upgrade_ibuf = false;
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2018-01-16 13:57:30 +02:00
|
|
|
switch (srv_operation) {
|
2023-03-31 21:32:41 +02:00
|
|
|
case SRV_OPERATION_NORMAL:
|
2023-03-23 16:26:17 +03:00
|
|
|
case SRV_OPERATION_EXPORT_RESTORED:
|
2018-01-16 13:57:30 +02:00
|
|
|
case SRV_OPERATION_RESTORE_EXPORT:
|
|
|
|
if (err != DB_SUCCESS) {
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
err = ibuf_upgrade_needed();
|
|
|
|
|
|
|
|
if (UNIV_UNLIKELY(err == DB_FAIL)) {
|
|
|
|
must_upgrade_ibuf = true;
|
|
|
|
err = ibuf_log_rebuild_if_needed();
|
2018-01-16 13:57:30 +02:00
|
|
|
}
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
err = dict_boot();
|
2018-02-20 15:10:03 +02:00
|
|
|
/* fall through */
|
|
|
|
case SRV_OPERATION_RESTORE:
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
2019-12-04 15:00:57 +02:00
|
|
|
srv_undo_tablespaces_active
|
|
|
|
= trx_rseg_get_n_undo_tablespaces();
|
2018-01-16 13:57:30 +02:00
|
|
|
break;
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
default:
|
2020-03-10 20:05:17 +02:00
|
|
|
ut_ad("wrong mariabackup mode" == 0);
|
2018-01-16 13:57:30 +02:00
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return srv_init_abort(err);
|
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
if (srv_force_recovery < SRV_FORCE_NO_LOG_REDO) {
|
|
|
|
/* Apply the hashed log records to the
|
|
|
|
respective file pages, for the last batch of
|
2023-04-25 12:00:06 +02:00
|
|
|
recv_group_scan_log_recs().
|
|
|
|
Since it may generate huge batch of threadpool tasks,
|
|
|
|
for read io task group, scale down thread creation rate
|
|
|
|
by temporarily restricting tpool concurrency.
|
|
|
|
*/
|
|
|
|
srv_thread_pool->set_concurrency(srv_n_read_io_threads);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
mysql_mutex_lock(&recv_sys.mutex);
|
2020-03-30 18:45:09 +03:00
|
|
|
recv_sys.apply(true);
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
mysql_mutex_unlock(&recv_sys.mutex);
|
MDEV-12253: Buffer pool blocks are accessed after they have been freed
Problem was that bpage was referenced after it was already freed
from LRU. Fixed by adding a new variable encrypted that is
passed down to buf_page_check_corrupt() and used in
buf_page_get_gen() to stop processing page read.
This patch should also address following test failures and
bugs:
MDEV-12419: IMPORT should not look up tablespace in
PageConverter::validate(). This is now removed.
MDEV-10099: encryption.innodb_onlinealter_encryption fails
sporadically in buildbot
MDEV-11420: encryption.innodb_encryption-page-compression
failed in buildbot
MDEV-11222: encryption.encrypt_and_grep failed in buildbot on P8
Removed dict_table_t::is_encrypted and dict_table_t::ibd_file_missing
and replaced these with dict_table_t::file_unreadable. Table
ibd file is missing if fil_get_space(space_id) returns NULL
and encrypted if not. Removed dict_table_t::is_corrupted field.
Ported FilSpace class from 10.2 and using that on buf_page_check_corrupt(),
buf_page_decrypt_after_read(), buf_page_encrypt_before_write(),
buf_dblwr_process(), buf_read_page(), dict_stats_save_defrag_stats().
Added test cases when enrypted page could be read while doing
redo log crash recovery. Also added test case for row compressed
blobs.
btr_cur_open_at_index_side_func(),
btr_cur_open_at_rnd_pos_func(): Avoid referencing block that is
NULL.
buf_page_get_zip(): Issue error if page read fails.
buf_page_get_gen(): Use dberr_t for error detection and
do not reference bpage after we hare freed it.
buf_mark_space_corrupt(): remove bpage from LRU also when
it is encrypted.
buf_page_check_corrupt(): @return DB_SUCCESS if page has
been read and is not corrupted,
DB_PAGE_CORRUPTED if page based on checksum check is corrupted,
DB_DECRYPTION_FAILED if page post encryption checksum matches but
after decryption normal page checksum does not match. In read
case only DB_SUCCESS is possible.
buf_page_io_complete(): use dberr_t for error handling.
buf_flush_write_block_low(),
buf_read_ahead_random(),
buf_read_page_async(),
buf_read_ahead_linear(),
buf_read_ibuf_merge_pages(),
buf_read_recv_pages(),
fil_aio_wait():
Issue error if page read fails.
btr_pcur_move_to_next_page(): Do not reference page if it is
NULL.
Introduced dict_table_t::is_readable() and dict_index_t::is_readable()
that will return true if tablespace exists and pages read from
tablespace are not corrupted or page decryption failed.
Removed buf_page_t::key_version. After page decryption the
key version is not removed from page frame. For unencrypted
pages, old key_version is removed at buf_page_encrypt_before_write()
dict_stats_update_transient_for_index(),
dict_stats_update_transient()
Do not continue if table decryption failed or table
is corrupted.
dict0stats.cc: Introduced a dict_stats_report_error function
to avoid code duplication.
fil_parse_write_crypt_data():
Check that key read from redo log entry is found from
encryption plugin and if it is not, refuse to start.
PageConverter::validate(): Removed access to fil_space_t as
tablespace is not available during import.
Fixed error code on innodb.innodb test.
Merged test cased innodb-bad-key-change5 and innodb-bad-key-shutdown
to innodb-bad-key-change2. Removed innodb-bad-key-change5 test.
Decreased unnecessary complexity on some long lasting tests.
Removed fil_inc_pending_ops(), fil_decr_pending_ops(),
fil_get_first_space(), fil_get_next_space(),
fil_get_first_space_safe(), fil_get_next_space_safe()
functions.
fil_space_verify_crypt_checksum(): Fixed bug found using ASAN
where FIL_PAGE_END_LSN_OLD_CHECKSUM field was incorrectly
accessed from row compressed tables. Fixed out of page frame
bug for row compressed tables in
fil_space_verify_crypt_checksum() found using ASAN. Incorrect
function was called for compressed table.
Added new tests for discard, rename table and drop (we should allow them
even when page decryption fails). Alter table rename is not allowed.
Added test for restart with innodb-force-recovery=1 when page read on
redo-recovery cant be decrypted. Added test for corrupted table where
both page data and FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION is corrupted.
Adjusted the test case innodb_bug14147491 so that it does not anymore
expect crash. Instead table is just mostly not usable.
fil0fil.h: fil_space_acquire_low is not visible function
and fil_space_acquire and fil_space_acquire_silent are
inline functions. FilSpace class uses fil_space_acquire_low
directly.
recv_apply_hashed_log_recs() does not return anything.
2017-04-26 15:19:16 +03:00
|
|
|
|
2023-04-25 12:00:06 +02:00
|
|
|
srv_thread_pool->set_concurrency();
|
MDEV-12253: Buffer pool blocks are accessed after they have been freed
Problem was that bpage was referenced after it was already freed
from LRU. Fixed by adding a new variable encrypted that is
passed down to buf_page_check_corrupt() and used in
buf_page_get_gen() to stop processing page read.
This patch should also address following test failures and
bugs:
MDEV-12419: IMPORT should not look up tablespace in
PageConverter::validate(). This is now removed.
MDEV-10099: encryption.innodb_onlinealter_encryption fails
sporadically in buildbot
MDEV-11420: encryption.innodb_encryption-page-compression
failed in buildbot
MDEV-11222: encryption.encrypt_and_grep failed in buildbot on P8
Removed dict_table_t::is_encrypted and dict_table_t::ibd_file_missing
and replaced these with dict_table_t::file_unreadable. Table
ibd file is missing if fil_get_space(space_id) returns NULL
and encrypted if not. Removed dict_table_t::is_corrupted field.
Ported FilSpace class from 10.2 and using that on buf_page_check_corrupt(),
buf_page_decrypt_after_read(), buf_page_encrypt_before_write(),
buf_dblwr_process(), buf_read_page(), dict_stats_save_defrag_stats().
Added test cases when enrypted page could be read while doing
redo log crash recovery. Also added test case for row compressed
blobs.
btr_cur_open_at_index_side_func(),
btr_cur_open_at_rnd_pos_func(): Avoid referencing block that is
NULL.
buf_page_get_zip(): Issue error if page read fails.
buf_page_get_gen(): Use dberr_t for error detection and
do not reference bpage after we hare freed it.
buf_mark_space_corrupt(): remove bpage from LRU also when
it is encrypted.
buf_page_check_corrupt(): @return DB_SUCCESS if page has
been read and is not corrupted,
DB_PAGE_CORRUPTED if page based on checksum check is corrupted,
DB_DECRYPTION_FAILED if page post encryption checksum matches but
after decryption normal page checksum does not match. In read
case only DB_SUCCESS is possible.
buf_page_io_complete(): use dberr_t for error handling.
buf_flush_write_block_low(),
buf_read_ahead_random(),
buf_read_page_async(),
buf_read_ahead_linear(),
buf_read_ibuf_merge_pages(),
buf_read_recv_pages(),
fil_aio_wait():
Issue error if page read fails.
btr_pcur_move_to_next_page(): Do not reference page if it is
NULL.
Introduced dict_table_t::is_readable() and dict_index_t::is_readable()
that will return true if tablespace exists and pages read from
tablespace are not corrupted or page decryption failed.
Removed buf_page_t::key_version. After page decryption the
key version is not removed from page frame. For unencrypted
pages, old key_version is removed at buf_page_encrypt_before_write()
dict_stats_update_transient_for_index(),
dict_stats_update_transient()
Do not continue if table decryption failed or table
is corrupted.
dict0stats.cc: Introduced a dict_stats_report_error function
to avoid code duplication.
fil_parse_write_crypt_data():
Check that key read from redo log entry is found from
encryption plugin and if it is not, refuse to start.
PageConverter::validate(): Removed access to fil_space_t as
tablespace is not available during import.
Fixed error code on innodb.innodb test.
Merged test cased innodb-bad-key-change5 and innodb-bad-key-shutdown
to innodb-bad-key-change2. Removed innodb-bad-key-change5 test.
Decreased unnecessary complexity on some long lasting tests.
Removed fil_inc_pending_ops(), fil_decr_pending_ops(),
fil_get_first_space(), fil_get_next_space(),
fil_get_first_space_safe(), fil_get_next_space_safe()
functions.
fil_space_verify_crypt_checksum(): Fixed bug found using ASAN
where FIL_PAGE_END_LSN_OLD_CHECKSUM field was incorrectly
accessed from row compressed tables. Fixed out of page frame
bug for row compressed tables in
fil_space_verify_crypt_checksum() found using ASAN. Incorrect
function was called for compressed table.
Added new tests for discard, rename table and drop (we should allow them
even when page decryption fails). Alter table rename is not allowed.
Added test for restart with innodb-force-recovery=1 when page read on
redo-recovery cant be decrypted. Added test for corrupted table where
both page data and FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION is corrupted.
Adjusted the test case innodb_bug14147491 so that it does not anymore
expect crash. Instead table is just mostly not usable.
fil0fil.h: fil_space_acquire_low is not visible function
and fil_space_acquire and fil_space_acquire_silent are
inline functions. FilSpace class uses fil_space_acquire_low
directly.
recv_apply_hashed_log_recs() does not return anything.
2017-04-26 15:19:16 +03:00
|
|
|
|
2020-12-04 16:18:04 +02:00
|
|
|
if (recv_sys.is_corrupt_log()
|
|
|
|
|| recv_sys.is_corrupt_fs()) {
|
2017-07-05 22:09:28 +03:00
|
|
|
return(srv_init_abort(DB_CORRUPTION));
|
MDEV-12253: Buffer pool blocks are accessed after they have been freed
Problem was that bpage was referenced after it was already freed
from LRU. Fixed by adding a new variable encrypted that is
passed down to buf_page_check_corrupt() and used in
buf_page_get_gen() to stop processing page read.
This patch should also address following test failures and
bugs:
MDEV-12419: IMPORT should not look up tablespace in
PageConverter::validate(). This is now removed.
MDEV-10099: encryption.innodb_onlinealter_encryption fails
sporadically in buildbot
MDEV-11420: encryption.innodb_encryption-page-compression
failed in buildbot
MDEV-11222: encryption.encrypt_and_grep failed in buildbot on P8
Removed dict_table_t::is_encrypted and dict_table_t::ibd_file_missing
and replaced these with dict_table_t::file_unreadable. Table
ibd file is missing if fil_get_space(space_id) returns NULL
and encrypted if not. Removed dict_table_t::is_corrupted field.
Ported FilSpace class from 10.2 and using that on buf_page_check_corrupt(),
buf_page_decrypt_after_read(), buf_page_encrypt_before_write(),
buf_dblwr_process(), buf_read_page(), dict_stats_save_defrag_stats().
Added test cases when enrypted page could be read while doing
redo log crash recovery. Also added test case for row compressed
blobs.
btr_cur_open_at_index_side_func(),
btr_cur_open_at_rnd_pos_func(): Avoid referencing block that is
NULL.
buf_page_get_zip(): Issue error if page read fails.
buf_page_get_gen(): Use dberr_t for error detection and
do not reference bpage after we hare freed it.
buf_mark_space_corrupt(): remove bpage from LRU also when
it is encrypted.
buf_page_check_corrupt(): @return DB_SUCCESS if page has
been read and is not corrupted,
DB_PAGE_CORRUPTED if page based on checksum check is corrupted,
DB_DECRYPTION_FAILED if page post encryption checksum matches but
after decryption normal page checksum does not match. In read
case only DB_SUCCESS is possible.
buf_page_io_complete(): use dberr_t for error handling.
buf_flush_write_block_low(),
buf_read_ahead_random(),
buf_read_page_async(),
buf_read_ahead_linear(),
buf_read_ibuf_merge_pages(),
buf_read_recv_pages(),
fil_aio_wait():
Issue error if page read fails.
btr_pcur_move_to_next_page(): Do not reference page if it is
NULL.
Introduced dict_table_t::is_readable() and dict_index_t::is_readable()
that will return true if tablespace exists and pages read from
tablespace are not corrupted or page decryption failed.
Removed buf_page_t::key_version. After page decryption the
key version is not removed from page frame. For unencrypted
pages, old key_version is removed at buf_page_encrypt_before_write()
dict_stats_update_transient_for_index(),
dict_stats_update_transient()
Do not continue if table decryption failed or table
is corrupted.
dict0stats.cc: Introduced a dict_stats_report_error function
to avoid code duplication.
fil_parse_write_crypt_data():
Check that key read from redo log entry is found from
encryption plugin and if it is not, refuse to start.
PageConverter::validate(): Removed access to fil_space_t as
tablespace is not available during import.
Fixed error code on innodb.innodb test.
Merged test cased innodb-bad-key-change5 and innodb-bad-key-shutdown
to innodb-bad-key-change2. Removed innodb-bad-key-change5 test.
Decreased unnecessary complexity on some long lasting tests.
Removed fil_inc_pending_ops(), fil_decr_pending_ops(),
fil_get_first_space(), fil_get_next_space(),
fil_get_first_space_safe(), fil_get_next_space_safe()
functions.
fil_space_verify_crypt_checksum(): Fixed bug found using ASAN
where FIL_PAGE_END_LSN_OLD_CHECKSUM field was incorrectly
accessed from row compressed tables. Fixed out of page frame
bug for row compressed tables in
fil_space_verify_crypt_checksum() found using ASAN. Incorrect
function was called for compressed table.
Added new tests for discard, rename table and drop (we should allow them
even when page decryption fails). Alter table rename is not allowed.
Added test for restart with innodb-force-recovery=1 when page read on
redo-recovery cant be decrypted. Added test for corrupted table where
both page data and FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION is corrupted.
Adjusted the test case innodb_bug14147491 so that it does not anymore
expect crash. Instead table is just mostly not usable.
fil0fil.h: fil_space_acquire_low is not visible function
and fil_space_acquire and fil_space_acquire_silent are
inline functions. FilSpace class uses fil_space_acquire_low
directly.
recv_apply_hashed_log_recs() does not return anything.
2017-04-26 15:19:16 +03:00
|
|
|
}
|
|
|
|
|
2023-12-04 09:45:53 +02:00
|
|
|
if (srv_operation != SRV_OPERATION_RESTORE
|
|
|
|
|| recv_needed_recovery) {
|
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
DBUG_PRINT("ib_log", ("apply completed"));
|
|
|
|
|
2023-12-04 09:45:53 +02:00
|
|
|
if (srv_operation != SRV_OPERATION_RESTORE) {
|
|
|
|
dict_sys.lock(SRW_LOCK_CALL);
|
|
|
|
dict_load_sys_table(dict_sys.sys_tables);
|
|
|
|
dict_sys.unlock();
|
|
|
|
|
|
|
|
if (UNIV_UNLIKELY(must_upgrade_ibuf)) {
|
|
|
|
dict_load_tablespaces(nullptr, true);
|
|
|
|
err = ibuf_upgrade();
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return srv_init_abort(err);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
dict_sys.lock(SRW_LOCK_CALL);
|
|
|
|
dict_load_sys_table(dict_sys.sys_columns);
|
|
|
|
dict_load_sys_table(dict_sys.sys_indexes);
|
|
|
|
dict_load_sys_table(dict_sys.sys_fields);
|
|
|
|
dict_sys.unlock();
|
|
|
|
dict_sys.load_sys_tables();
|
|
|
|
|
|
|
|
err = trx_lists_init_at_db_start();
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return srv_init_abort(err);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (recv_needed_recovery) {
|
|
|
|
trx_sys_print_mysql_binlog_offset();
|
|
|
|
}
|
|
|
|
} else if (recv_needed_recovery) {
|
|
|
|
err = trx_lists_init_at_db_start();
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return srv_init_abort(err);
|
|
|
|
}
|
2016-08-12 11:17:45 +03:00
|
|
|
trx_sys_print_mysql_binlog_offset();
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
MDEV-23855: Improve InnoDB log checkpoint performance
After MDEV-15053, MDEV-22871, MDEV-23399 shifted the scalability
bottleneck, log checkpoints became a new bottleneck.
If innodb_io_capacity is set low or innodb_max_dirty_pct_lwm is
set high and the workload fits in the buffer pool, the page cleaner
thread will perform very little flushing. When we reach the capacity
of the circular redo log file ib_logfile0 and must initiate a checkpoint,
some 'furious flushing' will be necessary. (If innodb_flush_sync=OFF,
then flushing would continue at the innodb_io_capacity rate, and
writers would be throttled.)
We have the best chance of advancing the checkpoint LSN immediately
after a page flush batch has been completed. Hence, it is best to
perform checkpoints after every batch in the page cleaner thread,
attempting to run once per second.
By initiating high-priority flushing in the page cleaner as early
as possible, we aim to make the throughput more stable.
The function buf_flush_wait_flushed() used to sleep for 10ms, hoping
that the page cleaner thread would do something during that time.
The observed end result was that a large number of threads that call
log_free_check() would end up sleeping while nothing useful is happening.
We will revise the design so that in the default innodb_flush_sync=ON
mode, buf_flush_wait_flushed() will wake up the page cleaner thread
to perform the necessary flushing, and it will wait for a signal from
the page cleaner thread.
If innodb_io_capacity is set to a low value (causing the page cleaner to
throttle its work), a write workload would initially perform well, until
the capacity of the circular ib_logfile0 is reached and log_free_check()
will trigger checkpoints. At that point, the extra waiting in
buf_flush_wait_flushed() will start reducing throughput.
The page cleaner thread will also initiate log checkpoints after each
buf_flush_lists() call, because that is the best point of time for
the checkpoint LSN to advance by the maximum amount.
Even in 'furious flushing' mode we invoke buf_flush_lists() with
innodb_io_capacity_max pages at a time, and at the start of each
batch (in the log_flush() callback function that runs in a separate
task) we will invoke os_aio_wait_until_no_pending_writes(). This
tweak allows the checkpoint to advance in smaller steps and
significantly reduces the maximum latency. On an Intel Optane 960
NVMe SSD on Linux, it reduced from 4.6 seconds to 74 milliseconds.
On Microsoft Windows with a slower SSD, it reduced from more than
180 seconds to 0.6 seconds.
We will make innodb_adaptive_flushing=OFF simply flush innodb_io_capacity
per second whenever the dirty proportion of buffer pool pages exceeds
innodb_max_dirty_pages_pct_lwm. For innodb_adaptive_flushing=ON we try
to make page_cleaner_flush_pages_recommendation() more consistent and
predictable: if we are below innodb_adaptive_flushing_lwm, let us flush
pages according to the return value of af_get_pct_for_dirty().
innodb_max_dirty_pages_pct_lwm: Revert the change of the default value
that was made in MDEV-23399. The value innodb_max_dirty_pages_pct_lwm=0
guarantees that a shutdown of an idle server will be fast. Users might
be surprised if normal shutdown suddenly became slower when upgrading
within a GA release series.
innodb_checkpoint_usec: Remove. The master task will no longer perform
periodic log checkpoints. It is the duty of the page cleaner thread.
log_sys.max_modified_age: Remove. The current span of the
buf_pool.flush_list expressed in LSN only matters for adaptive
flushing (outside the 'furious flushing' condition).
For the correctness of checkpoints, the only thing that matters is
the checkpoint age (log_sys.lsn - log_sys.last_checkpoint_lsn).
This run-time constant was also reported as log_max_modified_age_sync.
log_sys.max_checkpoint_age_async: Remove. This does not serve any
purpose, because the checkpoints will now be triggered by the page
cleaner thread. We will retain the log_sys.max_checkpoint_age limit
for engaging 'furious flushing'.
page_cleaner.slot: Remove. It turns out that
page_cleaner_slot.flush_list_time was duplicating
page_cleaner.slot.flush_time and page_cleaner.slot.flush_list_pass
was duplicating page_cleaner.flush_pass.
Likewise, there were some redundant monitor counters, because the
page cleaner thread no longer performs any buf_pool.LRU flushing, and
because there only is one buf_flush_page_cleaner thread.
buf_flush_sync_lsn: Protect writes by buf_pool.flush_list_mutex.
buf_pool_t::get_oldest_modification(): Add a parameter to specify the
return value when no persistent data pages are dirty. Require the
caller to hold buf_pool.flush_list_mutex.
log_buf_pool_get_oldest_modification(): Take the fall-back LSN
as a parameter. All callers will also invoke log_sys.get_lsn().
log_preflush_pool_modified_pages(): Replaced with buf_flush_wait_flushed().
buf_flush_wait_flushed(): Implement two limits. If not enough buffer pool
has been flushed, signal the page cleaner (unless innodb_flush_sync=OFF)
and wait for the page cleaner to complete. If the page cleaner
thread is not running (which can be the case durign shutdown),
initiate the flush and wait for it directly.
buf_flush_ahead(): If innodb_flush_sync=ON (the default),
submit a new buf_flush_sync_lsn target for the page cleaner
but do not wait for the flushing to finish.
log_get_capacity(), log_get_max_modified_age_async(): Remove, to make
it easier to see that af_get_pct_for_lsn() is not acquiring any mutexes.
page_cleaner_flush_pages_recommendation(): Protect all access to
buf_pool.flush_list with buf_pool.flush_list_mutex. Previously there
were some race conditions in the calculation.
buf_flush_sync_for_checkpoint(): New function to process
buf_flush_sync_lsn in the page cleaner thread. At the end of
each batch, we try to wake up any blocked buf_flush_wait_flushed().
If everything up to buf_flush_sync_lsn has been flushed, we will
reset buf_flush_sync_lsn=0. The page cleaner thread will keep
'furious flushing' until the limit is reached. Any threads that
are waiting in buf_flush_wait_flushed() will be able to resume
as soon as their own limit has been satisfied.
buf_flush_page_cleaner: Prioritize buf_flush_sync_lsn and do not
sleep as long as it is set. Do not update any page_cleaner statistics
for this special mode of operation. In the normal mode
(buf_flush_sync_lsn is not set for innodb_flush_sync=ON),
try to wake up once per second. No longer check whether
srv_inc_activity_count() has been called. After each batch,
try to perform a log checkpoint, because the best chances for
the checkpoint LSN to advance by the maximum amount are upon
completing a flushing batch.
log_t: Move buf_free, max_buf_free possibly to the same cache line
with log_sys.mutex.
log_margin_checkpoint_age(): Simplify the logic, and replace
a 0.1-second sleep with a call to buf_flush_wait_flushed() to
initiate flushing. Moved to the same compilation unit
with the only caller.
log_close(): Clean up the calculations. (Should be no functional
change.) Return whether flush-ahead is needed. Moved to the same
compilation unit with the only caller.
mtr_t::finish_write(): Return whether flush-ahead is needed.
mtr_t::commit(): Invoke buf_flush_ahead() when needed. Let us avoid
external calls in mtr_t::commit() and make the logic easier to follow
by having related code in a single compilation unit. Also, we will
invoke srv_stats.log_write_requests.inc() only once per
mini-transaction commit, while not holding mutexes.
log_checkpoint_margin(): Only care about log_sys.max_checkpoint_age.
Upon reaching log_sys.max_checkpoint_age where we must wait to prevent
the log from getting corrupted, let us wait for at most 1MiB of LSN
at a time, before rechecking the condition. This should allow writers
to proceed even if the redo log capacity has been reached and
'furious flushing' is in progress. We no longer care about
log_sys.max_modified_age_sync or log_sys.max_modified_age_async.
The log_sys.max_modified_age_sync could be a relic from the time when
there was a srv_master_thread that wrote dirty pages to data files.
Also, we no longer have any log_sys.max_checkpoint_age_async limit,
because log checkpoints will now be triggered by the page cleaner
thread upon completing buf_flush_lists().
log_set_capacity(): Simplify the calculations of the limit
(no functional change).
log_checkpoint_low(): Split from log_checkpoint(). Moved to the
same compilation unit with the caller.
log_make_checkpoint(): Only wait for everything to be flushed until
the current LSN.
create_log_file(): After checkpoint, invoke log_write_up_to()
to ensure that the FILE_CHECKPOINT record has been written.
This avoids ut_ad(!srv_log_file_created) in create_log_file_rename().
srv_start(): Do not call recv_recovery_from_checkpoint_start()
if the log has just been created. Set fil_system.space_id_reuse_warned
before dict_boot() has been executed, and clear it after recovery
has finished.
dict_boot(): Initialize fil_system.max_assigned_id.
srv_check_activity(): Remove. The activity count is counting transaction
commits and therefore mostly interesting for the purge of history.
BtrBulk::insert(): Do not explicitly wake up the page cleaner,
but do invoke srv_inc_activity_count(), because that counter is
still being used in buf_load_throttle_if_needed() for some
heuristics. (It might be cleaner to execute buf_load() in the
page cleaner thread!)
Reviewed by: Vladislav Vaintroub
2020-10-26 16:35:47 +02:00
|
|
|
fil_system.space_id_reuse_warned = false;
|
|
|
|
|
2017-01-26 14:05:00 +02:00
|
|
|
if (!srv_read_only_mode) {
|
2021-07-22 11:22:47 +03:00
|
|
|
const uint32_t flags = FSP_FLAGS_PAGE_SSIZE();
|
2022-10-24 20:46:43 +05:30
|
|
|
for (uint32_t id = srv_undo_space_id_start;
|
|
|
|
id <= srv_undo_tablespaces; id++) {
|
2018-03-27 11:49:57 +03:00
|
|
|
if (fil_space_t* space = fil_space_get(id)) {
|
|
|
|
fsp_flags_try_adjust(space, flags);
|
2017-01-26 14:05:00 +02:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (sum_of_new_sizes > 0) {
|
|
|
|
/* New data file(s) were added */
|
|
|
|
mtr.start();
|
2020-11-20 12:30:55 +02:00
|
|
|
mtr.x_lock_space(fil_system.sys_space);
|
2018-03-28 09:29:14 +03:00
|
|
|
buf_block_t* block = buf_page_get(
|
2019-02-06 19:50:11 +02:00
|
|
|
page_id_t(0, 0), 0,
|
2018-03-28 09:29:14 +03:00
|
|
|
RW_SX_LATCH, &mtr);
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
/* The first page of the system tablespace
|
|
|
|
should already have been successfully
|
|
|
|
accessed earlier during startup. */
|
|
|
|
ut_a(block);
|
2018-03-28 09:29:14 +03:00
|
|
|
ulint size = mach_read_from_4(
|
|
|
|
FSP_HEADER_OFFSET + FSP_SIZE
|
MDEV-27058: Reduce the size of buf_block_t and buf_page_t
buf_page_t::frame: Moved from buf_block_t::frame.
All 'thin' buf_page_t describing compressed-only ROW_FORMAT=COMPRESSED
pages will have frame=nullptr, while all 'fat' buf_block_t
will have a non-null frame pointing to aligned innodb_page_size bytes.
This eliminates the need for separate states for
BUF_BLOCK_FILE_PAGE and BUF_BLOCK_ZIP_PAGE.
buf_page_t::lock: Moved from buf_block_t::lock. That is, all block
descriptors will have a page latch. The IO_PIN state that was used
for discarding or creating the uncompressed page frame of a
ROW_FORMAT=COMPRESSED block is replaced by a combination of read-fix
and page X-latch.
page_zip_des_t::fix: Replaces state_, buf_fix_count_, io_fix_, status
of buf_page_t with a single std::atomic<uint32_t>. All modifications
will use store(), fetch_add(), fetch_sub(). This space was previously
wasted to alignment on 64-bit systems. We will use the following encoding
that combines a state (partly read-fix or write-fix) and a buffer-fix
count:
buf_page_t::NOT_USED=0 (previously BUF_BLOCK_NOT_USED)
buf_page_t::MEMORY=1 (previously BUF_BLOCK_MEMORY)
buf_page_t::REMOVE_HASH=2 (previously BUF_BLOCK_REMOVE_HASH)
buf_page_t::FREED=3 + fix: pages marked as freed in the file
buf_page_t::UNFIXED=1U<<29 + fix: normal pages
buf_page_t::IBUF_EXIST=2U<<29 + fix: normal pages; may need ibuf merge
buf_page_t::REINIT=3U<<29 + fix: reinitialized pages (skip doublewrite)
buf_page_t::READ_FIX=4U<<29 + fix: read-fixed pages (also X-latched)
buf_page_t::WRITE_FIX=5U<<29 + fix: write-fixed pages (also U-latched)
buf_page_t::WRITE_FIX_IBUF=6U<<29 + fix: write-fixed; may have ibuf
buf_page_t::WRITE_FIX_REINIT=7U<<29 + fix: write-fixed (no doublewrite)
buf_page_t::write_complete(): Change WRITE_FIX or WRITE_FIX_REINIT to
UNFIXED, and WRITE_FIX_IBUF to IBUF_EXIST, before releasing the U-latch.
buf_page_t::read_complete(): Renamed from buf_page_read_complete().
Change READ_FIX to UNFIXED or IBUF_EXIST, before releasing the X-latch.
buf_page_t::can_relocate(): If the page latch is being held or waited for,
or the block is buffer-fixed or io-fixed, return false. (The condition
on the page latch is new.)
Outside buf_page_get_gen(), buf_page_get_low() and buf_page_free(), we
will acquire the page latch before fix(), and unfix() before unlocking.
buf_page_t::flush(): Replaces buf_flush_page(). Optimize the
handling of FREED pages.
buf_pool_t::release_freed_page(): Assume that buf_pool.mutex is held
by the caller.
buf_page_t::is_read_fixed(), buf_page_t::is_write_fixed(): New predicates.
buf_page_get_low(): Ignore guesses that are read-fixed because they
may not yet be registered in buf_pool.page_hash and buf_pool.LRU.
buf_page_optimistic_get(): Acquire latch before buffer-fixing.
buf_page_make_young(): Leave read-fixed blocks alone, because they
might not be registered in buf_pool.LRU yet.
recv_sys_t::recover_deferred(), recv_sys_t::recover_low():
Possibly fix MDEV-26326, by holding a page X-latch instead of
only buffer-fixing the page.
2021-11-16 19:55:06 +02:00
|
|
|
+ block->page.frame);
|
2018-03-28 09:29:14 +03:00
|
|
|
ut_ad(size == fil_system.sys_space
|
|
|
|
->size_in_header);
|
|
|
|
size += sum_of_new_sizes;
|
2019-12-03 10:19:45 +02:00
|
|
|
mtr.write<4>(*block,
|
|
|
|
FSP_HEADER_OFFSET + FSP_SIZE
|
MDEV-27058: Reduce the size of buf_block_t and buf_page_t
buf_page_t::frame: Moved from buf_block_t::frame.
All 'thin' buf_page_t describing compressed-only ROW_FORMAT=COMPRESSED
pages will have frame=nullptr, while all 'fat' buf_block_t
will have a non-null frame pointing to aligned innodb_page_size bytes.
This eliminates the need for separate states for
BUF_BLOCK_FILE_PAGE and BUF_BLOCK_ZIP_PAGE.
buf_page_t::lock: Moved from buf_block_t::lock. That is, all block
descriptors will have a page latch. The IO_PIN state that was used
for discarding or creating the uncompressed page frame of a
ROW_FORMAT=COMPRESSED block is replaced by a combination of read-fix
and page X-latch.
page_zip_des_t::fix: Replaces state_, buf_fix_count_, io_fix_, status
of buf_page_t with a single std::atomic<uint32_t>. All modifications
will use store(), fetch_add(), fetch_sub(). This space was previously
wasted to alignment on 64-bit systems. We will use the following encoding
that combines a state (partly read-fix or write-fix) and a buffer-fix
count:
buf_page_t::NOT_USED=0 (previously BUF_BLOCK_NOT_USED)
buf_page_t::MEMORY=1 (previously BUF_BLOCK_MEMORY)
buf_page_t::REMOVE_HASH=2 (previously BUF_BLOCK_REMOVE_HASH)
buf_page_t::FREED=3 + fix: pages marked as freed in the file
buf_page_t::UNFIXED=1U<<29 + fix: normal pages
buf_page_t::IBUF_EXIST=2U<<29 + fix: normal pages; may need ibuf merge
buf_page_t::REINIT=3U<<29 + fix: reinitialized pages (skip doublewrite)
buf_page_t::READ_FIX=4U<<29 + fix: read-fixed pages (also X-latched)
buf_page_t::WRITE_FIX=5U<<29 + fix: write-fixed pages (also U-latched)
buf_page_t::WRITE_FIX_IBUF=6U<<29 + fix: write-fixed; may have ibuf
buf_page_t::WRITE_FIX_REINIT=7U<<29 + fix: write-fixed (no doublewrite)
buf_page_t::write_complete(): Change WRITE_FIX or WRITE_FIX_REINIT to
UNFIXED, and WRITE_FIX_IBUF to IBUF_EXIST, before releasing the U-latch.
buf_page_t::read_complete(): Renamed from buf_page_read_complete().
Change READ_FIX to UNFIXED or IBUF_EXIST, before releasing the X-latch.
buf_page_t::can_relocate(): If the page latch is being held or waited for,
or the block is buffer-fixed or io-fixed, return false. (The condition
on the page latch is new.)
Outside buf_page_get_gen(), buf_page_get_low() and buf_page_free(), we
will acquire the page latch before fix(), and unfix() before unlocking.
buf_page_t::flush(): Replaces buf_flush_page(). Optimize the
handling of FREED pages.
buf_pool_t::release_freed_page(): Assume that buf_pool.mutex is held
by the caller.
buf_page_t::is_read_fixed(), buf_page_t::is_write_fixed(): New predicates.
buf_page_get_low(): Ignore guesses that are read-fixed because they
may not yet be registered in buf_pool.page_hash and buf_pool.LRU.
buf_page_optimistic_get(): Acquire latch before buffer-fixing.
buf_page_make_young(): Leave read-fixed blocks alone, because they
might not be registered in buf_pool.LRU yet.
recv_sys_t::recover_deferred(), recv_sys_t::recover_low():
Possibly fix MDEV-26326, by holding a page X-latch instead of
only buffer-fixing the page.
2021-11-16 19:55:06 +02:00
|
|
|
+ block->page.frame, size);
|
2020-10-15 16:28:19 +03:00
|
|
|
fil_system.sys_space->size_in_header
|
|
|
|
= uint32_t(size);
|
2017-01-26 14:05:00 +02:00
|
|
|
mtr.commit();
|
2021-05-04 11:51:35 +03:00
|
|
|
log_write_up_to(mtr.commit_lsn(), true);
|
2017-01-26 14:05:00 +02:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2018-03-28 09:29:14 +03:00
|
|
|
#ifdef UNIV_DEBUG
|
|
|
|
{
|
|
|
|
mtr.start();
|
2019-02-06 19:50:11 +02:00
|
|
|
buf_block_t* block = buf_page_get(page_id_t(0, 0), 0,
|
2018-03-28 09:29:14 +03:00
|
|
|
RW_S_LATCH, &mtr);
|
|
|
|
ut_ad(mach_read_from_4(FSP_SIZE + FSP_HEADER_OFFSET
|
MDEV-27058: Reduce the size of buf_block_t and buf_page_t
buf_page_t::frame: Moved from buf_block_t::frame.
All 'thin' buf_page_t describing compressed-only ROW_FORMAT=COMPRESSED
pages will have frame=nullptr, while all 'fat' buf_block_t
will have a non-null frame pointing to aligned innodb_page_size bytes.
This eliminates the need for separate states for
BUF_BLOCK_FILE_PAGE and BUF_BLOCK_ZIP_PAGE.
buf_page_t::lock: Moved from buf_block_t::lock. That is, all block
descriptors will have a page latch. The IO_PIN state that was used
for discarding or creating the uncompressed page frame of a
ROW_FORMAT=COMPRESSED block is replaced by a combination of read-fix
and page X-latch.
page_zip_des_t::fix: Replaces state_, buf_fix_count_, io_fix_, status
of buf_page_t with a single std::atomic<uint32_t>. All modifications
will use store(), fetch_add(), fetch_sub(). This space was previously
wasted to alignment on 64-bit systems. We will use the following encoding
that combines a state (partly read-fix or write-fix) and a buffer-fix
count:
buf_page_t::NOT_USED=0 (previously BUF_BLOCK_NOT_USED)
buf_page_t::MEMORY=1 (previously BUF_BLOCK_MEMORY)
buf_page_t::REMOVE_HASH=2 (previously BUF_BLOCK_REMOVE_HASH)
buf_page_t::FREED=3 + fix: pages marked as freed in the file
buf_page_t::UNFIXED=1U<<29 + fix: normal pages
buf_page_t::IBUF_EXIST=2U<<29 + fix: normal pages; may need ibuf merge
buf_page_t::REINIT=3U<<29 + fix: reinitialized pages (skip doublewrite)
buf_page_t::READ_FIX=4U<<29 + fix: read-fixed pages (also X-latched)
buf_page_t::WRITE_FIX=5U<<29 + fix: write-fixed pages (also U-latched)
buf_page_t::WRITE_FIX_IBUF=6U<<29 + fix: write-fixed; may have ibuf
buf_page_t::WRITE_FIX_REINIT=7U<<29 + fix: write-fixed (no doublewrite)
buf_page_t::write_complete(): Change WRITE_FIX or WRITE_FIX_REINIT to
UNFIXED, and WRITE_FIX_IBUF to IBUF_EXIST, before releasing the U-latch.
buf_page_t::read_complete(): Renamed from buf_page_read_complete().
Change READ_FIX to UNFIXED or IBUF_EXIST, before releasing the X-latch.
buf_page_t::can_relocate(): If the page latch is being held or waited for,
or the block is buffer-fixed or io-fixed, return false. (The condition
on the page latch is new.)
Outside buf_page_get_gen(), buf_page_get_low() and buf_page_free(), we
will acquire the page latch before fix(), and unfix() before unlocking.
buf_page_t::flush(): Replaces buf_flush_page(). Optimize the
handling of FREED pages.
buf_pool_t::release_freed_page(): Assume that buf_pool.mutex is held
by the caller.
buf_page_t::is_read_fixed(), buf_page_t::is_write_fixed(): New predicates.
buf_page_get_low(): Ignore guesses that are read-fixed because they
may not yet be registered in buf_pool.page_hash and buf_pool.LRU.
buf_page_optimistic_get(): Acquire latch before buffer-fixing.
buf_page_make_young(): Leave read-fixed blocks alone, because they
might not be registered in buf_pool.LRU yet.
recv_sys_t::recover_deferred(), recv_sys_t::recover_low():
Possibly fix MDEV-26326, by holding a page X-latch instead of
only buffer-fixing the page.
2021-11-16 19:55:06 +02:00
|
|
|
+ block->page.frame)
|
2018-03-28 09:29:14 +03:00
|
|
|
== fil_system.sys_space->size_in_header);
|
|
|
|
mtr.commit();
|
|
|
|
}
|
|
|
|
#endif
|
2017-01-26 14:05:00 +02:00
|
|
|
const ulint tablespace_size_in_header
|
2018-03-28 09:29:14 +03:00
|
|
|
= fil_system.sys_space->size_in_header;
|
2017-01-26 14:05:00 +02:00
|
|
|
const ulint sum_of_data_file_sizes
|
|
|
|
= srv_sys_space.get_sum_of_sizes();
|
|
|
|
/* Compare the system tablespace file size to what is
|
2017-06-08 12:45:08 +03:00
|
|
|
stored in FSP_SIZE. In srv_sys_space.open_or_create()
|
2017-01-26 14:05:00 +02:00
|
|
|
we already checked that the file sizes match the
|
|
|
|
innodb_data_file_path specification. */
|
|
|
|
if (srv_read_only_mode
|
|
|
|
|| sum_of_data_file_sizes == tablespace_size_in_header) {
|
|
|
|
/* Do not complain about the size. */
|
|
|
|
} else if (!srv_sys_space.can_auto_extend_last_file()
|
|
|
|
|| sum_of_data_file_sizes
|
|
|
|
< tablespace_size_in_header) {
|
|
|
|
ib::error() << "Tablespace size stored in header is "
|
|
|
|
<< tablespace_size_in_header
|
|
|
|
<< " pages, but the sum of data file sizes is "
|
|
|
|
<< sum_of_data_file_sizes << " pages";
|
|
|
|
|
|
|
|
if (srv_force_recovery == 0
|
|
|
|
&& sum_of_data_file_sizes
|
|
|
|
< tablespace_size_in_header) {
|
|
|
|
ib::error() <<
|
|
|
|
"Cannot start InnoDB. The tail of"
|
|
|
|
" the system tablespace is"
|
|
|
|
" missing. Have you edited"
|
|
|
|
" innodb_data_file_path in my.cnf"
|
|
|
|
" in an inappropriate way, removing"
|
|
|
|
" data files from there?"
|
|
|
|
" You can set innodb_force_recovery=1"
|
|
|
|
" in my.cnf to force"
|
|
|
|
" a startup if you are trying to"
|
|
|
|
" recover a badly corrupt database.";
|
|
|
|
|
|
|
|
return(srv_init_abort(DB_ERROR));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2023-04-12 15:50:08 +03:00
|
|
|
if (srv_operation > SRV_OPERATION_EXPORT_RESTORED) {
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
ut_ad(srv_operation == SRV_OPERATION_RESTORE_EXPORT
|
|
|
|
|| srv_operation == SRV_OPERATION_RESTORE);
|
MDEV-12548 Initial implementation of Mariabackup for MariaDB 10.2
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
2017-06-30 10:49:37 +03:00
|
|
|
return(err);
|
|
|
|
}
|
|
|
|
|
2017-02-10 12:11:42 +02:00
|
|
|
/* Upgrade or resize or rebuild the redo logs before
|
|
|
|
generating any dirty pages, so that the old redo log
|
2020-01-12 02:05:28 +07:00
|
|
|
file will not be written to. */
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
err = srv_log_rebuild_if_needed();
|
2017-02-10 12:11:42 +02:00
|
|
|
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return(srv_init_abort(err));
|
2017-02-10 12:11:42 +02:00
|
|
|
}
|
2023-03-16 13:39:23 +02:00
|
|
|
|
|
|
|
recv_sys.debug_free();
|
2019-05-23 17:34:08 +03:00
|
|
|
}
|
|
|
|
|
|
|
|
ut_ad(err == DB_SUCCESS);
|
|
|
|
ut_a(sum_of_new_sizes != ULINT_UNDEFINED);
|
|
|
|
|
|
|
|
/* Create the doublewrite buffer to a new tablespace */
|
|
|
|
if (!srv_read_only_mode && srv_force_recovery < SRV_FORCE_NO_TRX_UNDO
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
&& !buf_dblwr.create()) {
|
2019-05-23 17:34:08 +03:00
|
|
|
return(srv_init_abort(DB_ERROR));
|
|
|
|
}
|
|
|
|
|
2022-10-24 20:46:43 +05:30
|
|
|
/* Recreate the undo tablespaces */
|
|
|
|
if (!high_level_read_only) {
|
|
|
|
err = srv_undo_tablespaces_reinitialize();
|
|
|
|
if (err) {
|
|
|
|
return srv_init_abort(err);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
srv_undo_tablespaces = srv_undo_tablespaces_open;
|
|
|
|
|
2019-05-23 17:34:08 +03:00
|
|
|
/* Here the double write buffer has already been created and so
|
|
|
|
any new rollback segments will be allocated after the double
|
|
|
|
write buffer. The default segment should already exist.
|
|
|
|
We create the new segments only if it's a new database or
|
|
|
|
the database was shutdown cleanly. */
|
2017-02-10 12:11:42 +02:00
|
|
|
|
2019-05-23 17:34:08 +03:00
|
|
|
/* Note: When creating the extra rollback segments during an upgrade
|
|
|
|
we violate the latching order, even if the change buffer is empty.
|
2020-12-04 19:02:58 +02:00
|
|
|
It cannot create a deadlock because we are still
|
2019-05-23 17:34:08 +03:00
|
|
|
running in single threaded mode essentially. Only the IO threads
|
|
|
|
should be running at this stage. */
|
|
|
|
|
|
|
|
if (!trx_sys_create_rsegs()) {
|
|
|
|
return(srv_init_abort(DB_ERROR));
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!create_new_db) {
|
2019-11-28 16:35:20 +02:00
|
|
|
ut_ad(high_level_read_only
|
MDEV-25683 Atomic DDL: With innodb_force_recovery=3 InnoDB: Trying to load index but the index tree has been freed
The purpose of the parameter innodb_force_recovery is to allow some
data to be dumped from a corrupted database. Its values used to be
as follows:
innodb_force_recovery=0: normal (default)
innodb_force_recovery=1: ignore (skip log for) corrupted pages or
missing data files when applying the redo log
innodb_force_recovery=2: additionally, disable background tasks
(such as the purge of committed undo logs)
innodb_force_recovery=3: additionally, disable the rollback of
recovered incomplete (not committed or XA PREPARE) transactions
innodb_force_recovery=4: same as 3 (since MDEV-19514 in MariaDB 10.5)
innodb_force_recovery=5: additionally, do not process any undo log,
disallow any writes, and force READ UNCOMMITTED isolation level
innodb_force_recovery=6: additionally, pretend that ib_logfile0 does
not exist (prevent any recovery). Never use this!
The bad thing that happens with innodb_force_recovery=3 and
innodb_force_recovery=4 is that also the rollback of any recovered
DDL transaction will be skipped. This would break the DDL log recovery
that was introduced in MDEV-17567.
For one data directory sample, the DDL log recovery would hangs due to
a conflict on the InnoDB SYS_TABLES table, because the lock holder
transaction was not rolled back due to innodb_force_recovery=3.
Fix: Make innodb_force_recovery=3 skip the DML transaction rollback only,
and make innodb_force_recovery=4 (renamed to SRV_FORCE_NO_DDL_UNDO)
behave like innodb_force_recovery=3 used to (skip the rollback of all
recovered transactions, both DML and DDL).
Startup with innodb_force_recovery=4 will be unaffected by this change.
(There may be hangs, possibly preceded by messages about failing to
load an index.)
Side note: With innodb_force_recovery=5, any DDL log for InnoDB tables
will be essentially ignored by InnoDB, but the server will start up.
2021-10-29 10:20:58 +03:00
|
|
|
|| srv_force_recovery < SRV_FORCE_NO_UNDO_LOG_SCAN);
|
2017-02-10 12:11:42 +02:00
|
|
|
|
|
|
|
/* Validate a few system page types that were left
|
2019-05-23 17:34:08 +03:00
|
|
|
uninitialized before MySQL or MariaDB 5.5. */
|
2019-11-28 16:22:53 +02:00
|
|
|
if (!high_level_read_only
|
|
|
|
&& !fil_system.sys_space->full_crc32()) {
|
2017-02-10 12:11:42 +02:00
|
|
|
buf_block_t* block;
|
|
|
|
mtr.start();
|
|
|
|
/* Bitmap page types will be reset in
|
|
|
|
buf_dblwr_check_block() without redo logging. */
|
|
|
|
block = buf_page_get(
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
page_id_t(0, FSP_IBUF_HEADER_PAGE_NO),
|
2019-02-06 19:50:11 +02:00
|
|
|
0, RW_X_LATCH, &mtr);
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
if (UNIV_UNLIKELY(!block)) {
|
|
|
|
corrupted_old_page:
|
|
|
|
mtr.commit();
|
|
|
|
return srv_init_abort(DB_CORRUPTION);
|
|
|
|
}
|
2018-10-18 18:23:12 +03:00
|
|
|
fil_block_check_type(*block, FIL_PAGE_TYPE_SYS, &mtr);
|
2017-02-10 12:11:42 +02:00
|
|
|
/* Already MySQL 3.23.53 initialized
|
|
|
|
FSP_IBUF_TREE_ROOT_PAGE_NO to
|
|
|
|
FIL_PAGE_INDEX. No need to reset that one. */
|
|
|
|
block = buf_page_get(
|
|
|
|
page_id_t(TRX_SYS_SPACE, TRX_SYS_PAGE_NO),
|
2019-02-06 19:50:11 +02:00
|
|
|
0, RW_X_LATCH, &mtr);
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
if (UNIV_UNLIKELY(!block)) {
|
|
|
|
goto corrupted_old_page;
|
|
|
|
}
|
2018-10-18 18:23:12 +03:00
|
|
|
fil_block_check_type(*block, FIL_PAGE_TYPE_TRX_SYS,
|
2017-02-10 12:11:42 +02:00
|
|
|
&mtr);
|
|
|
|
block = buf_page_get(
|
|
|
|
page_id_t(TRX_SYS_SPACE,
|
|
|
|
FSP_FIRST_RSEG_PAGE_NO),
|
2019-02-06 19:50:11 +02:00
|
|
|
0, RW_X_LATCH, &mtr);
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
if (UNIV_UNLIKELY(!block)) {
|
|
|
|
goto corrupted_old_page;
|
|
|
|
}
|
2018-10-18 18:23:12 +03:00
|
|
|
fil_block_check_type(*block, FIL_PAGE_TYPE_SYS, &mtr);
|
2017-02-10 12:11:42 +02:00
|
|
|
block = buf_page_get(
|
|
|
|
page_id_t(TRX_SYS_SPACE, FSP_DICT_HDR_PAGE_NO),
|
2019-02-06 19:50:11 +02:00
|
|
|
0, RW_X_LATCH, &mtr);
|
MDEV-13542: Crashing on corrupted page is unhelpful
The approach to handling corruption that was chosen by Oracle in
commit 177d8b0c125b841c0650d27d735e3b87509dc286
is not really useful. Not only did it actually fail to prevent InnoDB
from crashing, but it is making things worse by blocking attempts to
rescue data from or rebuild a partially readable table.
We will try to prevent crashes in a different way: by propagating
errors up the call stack. We will never mark the clustered index
persistently corrupted, so that data recovery may be attempted by
reading from the table, or by rebuilding the table.
This should also fix MDEV-13680 (crash on btr_page_alloc() failure);
it was extensively tested with innodb_file_per_table=0 and a
non-autoextend system tablespace.
We should now avoid crashes in many cases, such as when a page
cannot be read or allocated, or an inconsistency is detected when
attempting to update multiple pages. We will not crash on double-free,
such as on the recovery of DDL in system tablespace in case something
was corrupted.
Crashes on corrupted data are still possible. The fault injection mechanism
that is introduced in the subsequent commit may help catch more of them.
buf_page_import_corrupt_failure: Remove the fault injection, and instead
corrupt some pages using Perl code in the tests.
btr_cur_pessimistic_insert(): Always reserve extents (except for the
change buffer), in order to prevent a subsequent allocation failure.
btr_pcur_open_at_rnd_pos(): Merged to the only caller ibuf_merge_pages().
btr_assert_not_corrupted(), btr_corruption_report(): Remove.
Similar checks are already part of btr_block_get().
FSEG_MAGIC_N_BYTES: Replaces FSEG_MAGIC_N_VALUE.
dict_hdr_get(), trx_rsegf_get_new(), trx_undo_page_get(),
trx_undo_page_get_s_latched(): Replaced with error-checking calls.
trx_rseg_t::get(mtr_t*): Replaces trx_rsegf_get().
trx_rseg_header_create(): Let the caller update the TRX_SYS page if needed.
trx_sys_create_sys_pages(): Merged with trx_sysf_create().
dict_check_tablespaces_and_store_max_id(): Do not access
DICT_HDR_MAX_SPACE_ID, because it was already recovered in dict_boot().
Merge dict_check_sys_tables() with this function.
dir_pathname(): Replaces os_file_make_new_pathname().
row_undo_ins_remove_sec(): Do not modify the undo page by adding
a terminating NUL byte to the record.
btr_decryption_failed(): Report decryption failures
dict_set_corrupted_by_space(), dict_set_encrypted_by_space(),
dict_set_corrupted_index_cache_only(): Remove.
dict_set_corrupted(): Remove the constant parameter dict_locked=false.
Never flag the clustered index corrupted in SYS_INDEXES, because
that would deny further access to the table. It might be possible to
repair the table by executing ALTER TABLE or OPTIMIZE TABLE, in case
no B-tree leaf page is corrupted.
dict_table_skip_corrupt_index(), dict_table_next_uncorrupted_index(),
row_purge_skip_uncommitted_virtual_index(): Remove, and refactor
the callers to read dict_index_t::type only once.
dict_table_is_corrupted(): Remove.
dict_index_t::is_btree(): Determine if the index is a valid B-tree.
BUF_GET_NO_LATCH, BUF_EVICT_IF_IN_POOL: Remove.
UNIV_BTR_DEBUG: Remove. Any inconsistency will no longer trigger
assertion failures, but error codes being returned.
buf_corrupt_page_release(): Replaced with a direct call to
buf_pool.corrupted_evict().
fil_invalid_page_access_msg(): Never crash on an invalid read;
let the caller of buf_page_get_gen() decide.
btr_pcur_t::restore_position(): Propagate failure status to the caller
by returning CORRUPTED.
opt_search_plan_for_table(): Simplify the code.
row_purge_del_mark(), row_purge_upd_exist_or_extern_func(),
row_undo_ins_remove_sec_rec(), row_undo_mod_upd_del_sec(),
row_undo_mod_del_mark_sec(): Avoid mem_heap_create()/mem_heap_free()
when no secondary indexes exist.
row_undo_mod_upd_exist_sec(): Simplify the code.
row_upd_clust_step(), dict_load_table_one(): Return DB_TABLE_CORRUPT
if the clustered index (and therefore the table) is corrupted, similar
to what we do in row_insert_for_mysql().
fut_get_ptr(): Replace with buf_page_get_gen() calls.
buf_page_get_gen(): Return nullptr and *err=DB_CORRUPTION
if the page is marked as freed. For other modes than
BUF_GET_POSSIBLY_FREED or BUF_PEEK_IF_IN_POOL this will
trigger a debug assertion failure. For BUF_GET_POSSIBLY_FREED,
we will return nullptr for freed pages, so that the callers
can be simplified. The purge of transaction history will be
a new user of BUF_GET_POSSIBLY_FREED, to avoid crashes on
corrupted data.
buf_page_get_low(): Never crash on a corrupted page, but simply
return nullptr.
fseg_page_is_allocated(): Replaces fseg_page_is_free().
fts_drop_common_tables(): Return an error if the transaction
was rolled back.
fil_space_t::set_corrupted(): Report a tablespace as corrupted if
it was not reported already.
fil_space_t::io(): Invoke fil_space_t::set_corrupted() to report
out-of-bounds page access or other errors.
Clean up mtr_t::page_lock()
buf_page_get_low(): Validate the page identifier (to check for
recently read corrupted pages) after acquiring the page latch.
buf_page_t::read_complete(): Flag uninitialized (all-zero) pages
with DB_FAIL. Return DB_PAGE_CORRUPTED on page number mismatch.
mtr_t::defer_drop_ahi(): Renamed from mtr_defer_drop_ahi().
recv_sys_t::free_corrupted_page(): Only set_corrupt_fs()
if any log records exist for the page. We do not mind if read-ahead
produces corrupted (or all-zero) pages that were not actually needed
during recovery.
recv_recover_page(): Return whether the operation succeeded.
recv_sys_t::recover_low(): Simplify the logic. Check for recovery error.
Thanks to Matthias Leich for testing this extensively and to the
authors of https://rr-project.org for making it easy to diagnose
and fix any failures that were found during the testing.
2022-06-06 14:03:22 +03:00
|
|
|
if (UNIV_UNLIKELY(!block)) {
|
|
|
|
goto corrupted_old_page;
|
|
|
|
}
|
2018-10-18 18:23:12 +03:00
|
|
|
fil_block_check_type(*block, FIL_PAGE_TYPE_SYS, &mtr);
|
2017-02-10 12:11:42 +02:00
|
|
|
mtr.commit();
|
|
|
|
}
|
|
|
|
|
2019-11-28 16:35:20 +02:00
|
|
|
/* Roll back any recovered data dictionary
|
|
|
|
transactions, so that the data dictionary tables will
|
|
|
|
be free of any locks. The data dictionary latch
|
|
|
|
should guarantee that there is at most one data
|
|
|
|
dictionary transaction active at a time. */
|
|
|
|
if (!high_level_read_only
|
MDEV-25683 Atomic DDL: With innodb_force_recovery=3 InnoDB: Trying to load index but the index tree has been freed
The purpose of the parameter innodb_force_recovery is to allow some
data to be dumped from a corrupted database. Its values used to be
as follows:
innodb_force_recovery=0: normal (default)
innodb_force_recovery=1: ignore (skip log for) corrupted pages or
missing data files when applying the redo log
innodb_force_recovery=2: additionally, disable background tasks
(such as the purge of committed undo logs)
innodb_force_recovery=3: additionally, disable the rollback of
recovered incomplete (not committed or XA PREPARE) transactions
innodb_force_recovery=4: same as 3 (since MDEV-19514 in MariaDB 10.5)
innodb_force_recovery=5: additionally, do not process any undo log,
disallow any writes, and force READ UNCOMMITTED isolation level
innodb_force_recovery=6: additionally, pretend that ib_logfile0 does
not exist (prevent any recovery). Never use this!
The bad thing that happens with innodb_force_recovery=3 and
innodb_force_recovery=4 is that also the rollback of any recovered
DDL transaction will be skipped. This would break the DDL log recovery
that was introduced in MDEV-17567.
For one data directory sample, the DDL log recovery would hangs due to
a conflict on the InnoDB SYS_TABLES table, because the lock holder
transaction was not rolled back due to innodb_force_recovery=3.
Fix: Make innodb_force_recovery=3 skip the DML transaction rollback only,
and make innodb_force_recovery=4 (renamed to SRV_FORCE_NO_DDL_UNDO)
behave like innodb_force_recovery=3 used to (skip the rollback of all
recovered transactions, both DML and DDL).
Startup with innodb_force_recovery=4 will be unaffected by this change.
(There may be hangs, possibly preceded by messages about failing to
load an index.)
Side note: With innodb_force_recovery=5, any DDL log for InnoDB tables
will be essentially ignored by InnoDB, but the server will start up.
2021-10-29 10:20:58 +03:00
|
|
|
&& srv_force_recovery <= SRV_FORCE_NO_TRX_UNDO) {
|
2019-08-23 08:06:17 +03:00
|
|
|
/* If the following call is ever removed, the
|
|
|
|
first-time ha_innobase::open() must hold (or
|
|
|
|
acquire and release) a table lock that
|
|
|
|
conflicts with trx_resurrect_table_locks(), to
|
2019-11-28 16:35:20 +02:00
|
|
|
ensure that any recovered incomplete ALTER
|
|
|
|
TABLE will have been rolled back. Otherwise,
|
|
|
|
dict_table_t::instant could be cleared by
|
|
|
|
rollback invoking
|
|
|
|
dict_index_t::clear_instant_alter() while open
|
|
|
|
table handles exist in client connections. */
|
2017-12-21 15:45:40 +04:00
|
|
|
trx_rollback_recovered(false);
|
2017-02-10 12:11:42 +02:00
|
|
|
}
|
|
|
|
|
MDEV-25683 Atomic DDL: With innodb_force_recovery=3 InnoDB: Trying to load index but the index tree has been freed
The purpose of the parameter innodb_force_recovery is to allow some
data to be dumped from a corrupted database. Its values used to be
as follows:
innodb_force_recovery=0: normal (default)
innodb_force_recovery=1: ignore (skip log for) corrupted pages or
missing data files when applying the redo log
innodb_force_recovery=2: additionally, disable background tasks
(such as the purge of committed undo logs)
innodb_force_recovery=3: additionally, disable the rollback of
recovered incomplete (not committed or XA PREPARE) transactions
innodb_force_recovery=4: same as 3 (since MDEV-19514 in MariaDB 10.5)
innodb_force_recovery=5: additionally, do not process any undo log,
disallow any writes, and force READ UNCOMMITTED isolation level
innodb_force_recovery=6: additionally, pretend that ib_logfile0 does
not exist (prevent any recovery). Never use this!
The bad thing that happens with innodb_force_recovery=3 and
innodb_force_recovery=4 is that also the rollback of any recovered
DDL transaction will be skipped. This would break the DDL log recovery
that was introduced in MDEV-17567.
For one data directory sample, the DDL log recovery would hangs due to
a conflict on the InnoDB SYS_TABLES table, because the lock holder
transaction was not rolled back due to innodb_force_recovery=3.
Fix: Make innodb_force_recovery=3 skip the DML transaction rollback only,
and make innodb_force_recovery=4 (renamed to SRV_FORCE_NO_DDL_UNDO)
behave like innodb_force_recovery=3 used to (skip the rollback of all
recovered transactions, both DML and DDL).
Startup with innodb_force_recovery=4 will be unaffected by this change.
(There may be hangs, possibly preceded by messages about failing to
load an index.)
Side note: With innodb_force_recovery=5, any DDL log for InnoDB tables
will be essentially ignored by InnoDB, but the server will start up.
2021-10-29 10:20:58 +03:00
|
|
|
if (srv_force_recovery < SRV_FORCE_NO_UNDO_LOG_SCAN) {
|
MDEV-29694 Remove the InnoDB change buffer
The purpose of the change buffer was to reduce random disk access,
which could be useful on rotational storage, but maybe less so on
solid-state storage.
When we wished to
(1) insert a record into a non-unique secondary index,
(2) delete-mark a secondary index record,
(3) delete a secondary index record as part of purge (but not ROLLBACK),
and the B-tree leaf page where the record belongs to is not in the buffer
pool, we inserted a record into the change buffer B-tree, indexed by
the page identifier. When the page was eventually read into the buffer
pool, we looked up the change buffer B-tree for any modifications to the
page, applied these upon the completion of the read operation. This
was called the insert buffer merge.
We remove the change buffer, because it has been the source of
various hard-to-reproduce corruption bugs, including those fixed in
commit 5b9ee8d8193a8c7a8ebdd35eedcadc3ae78e7fc1 and
commit 165564d3c33ae3d677d70644a83afcb744bdbf65 but not limited to them.
A downgrade will fail with a clear message starting with
commit db14eb16f9977453467ec4765f481bb2f71814ba (MDEV-30106).
buf_page_t::state: Merge IBUF_EXIST to UNFIXED and
WRITE_FIX_IBUF to WRITE_FIX.
buf_pool_t::watch[]: Remove.
trx_t: Move isolation_level, check_foreigns, check_unique_secondary,
bulk_insert into the same bit-field. The only purpose of
trx_t::check_unique_secondary is to enable bulk insert into an
empty table. It no longer enables insert buffering for UNIQUE INDEX.
btr_cur_t::thr: Remove. This field was originally needed for change
buffering. Later, its use was extended to cover SPATIAL INDEX.
Much of the time, rtr_info::thr holds this field. When it does not,
we will add parameters to SPATIAL INDEX specific functions.
ibuf_upgrade_needed(): Check if the change buffer needs to be updated.
ibuf_upgrade(): Merge and upgrade the change buffer after all redo log
has been applied. Free any pages consumed by the change buffer, and
zero out the change buffer root page to mark the upgrade completed,
and to prevent a downgrade to an earlier version.
dict_load_tablespaces(): Renamed from
dict_check_tablespaces_and_store_max_id(). This needs to be invoked
before ibuf_upgrade().
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
btr_page_alloc(): Renamed from btr_page_alloc_low(). We no longer
allocate any change buffer pages.
btr_cur_open_at_rnd_pos(): Specialize for use in persistent statistics.
The change buffer merge does not need this function anymore.
row_search_index_entry(), btr_lift_page_up(): Add a parameter thr
for the SPATIAL INDEX case.
rtr_page_split_and_insert(): Specialized from btr_page_split_and_insert().
rtr_root_raise_and_insert(): Specialized from btr_root_raise_and_insert().
Note: The support for upgrading from the MySQL 3.23 or MySQL 4.0
change buffer format that predates the MySQL 4.1 introduction of
the option innodb_file_per_table was removed in MySQL 5.6.5
as part of mysql/mysql-server@69b6241a79876ae98bb0c9dce7c8d8799d6ad273
and MariaDB 10.0.11 as part of 1d0f70c2f894b27e98773a282871d32802f67964.
In the tests innodb.log_upgrade and innodb.log_corruption, we create
valid (upgraded) change buffer pages.
Tested by: Matthias Leich
2023-01-11 17:59:36 +02:00
|
|
|
dict_load_tablespaces();
|
2016-08-12 11:17:45 +03:00
|
|
|
}
|
2014-08-25 13:35:33 +03:00
|
|
|
|
2019-05-23 17:34:08 +03:00
|
|
|
if (srv_force_recovery < SRV_FORCE_NO_TRX_UNDO
|
|
|
|
&& !srv_read_only_mode) {
|
|
|
|
/* Drop partially created indexes. */
|
|
|
|
row_merge_drop_temp_indexes();
|
|
|
|
/* Rollback incomplete non-DDL transactions */
|
|
|
|
trx_rollback_is_active = true;
|
2021-03-17 10:03:06 +03:00
|
|
|
srv_thread_pool->submit_task(&rollback_all_recovered_task);
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
srv_startup_is_before_trx_rollback_phase = false;
|
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
if (!srv_read_only_mode) {
|
2018-11-20 15:19:32 +03:00
|
|
|
DBUG_EXECUTE_IF("innodb_skip_monitors", goto skip_monitors;);
|
2019-10-29 22:37:12 +01:00
|
|
|
/* Create the task which warns of long semaphore waits */
|
2020-11-25 16:54:00 +02:00
|
|
|
srv_start_periodic_timer(srv_monitor_timer, srv_monitor_task,
|
|
|
|
SRV_MONITOR_INTERVAL);
|
2019-10-29 22:37:12 +01:00
|
|
|
|
2018-11-20 15:19:32 +03:00
|
|
|
#ifndef DBUG_OFF
|
|
|
|
skip_monitors:
|
|
|
|
#endif
|
2018-02-22 09:49:50 +02:00
|
|
|
ut_ad(srv_force_recovery >= SRV_FORCE_NO_UNDO_LOG_SCAN
|
2018-05-15 14:39:50 +03:00
|
|
|
|| !purge_sys.enabled());
|
MDEV-12288 Reset DB_TRX_ID when the history is removed, to speed up MVCC
Let InnoDB purge reset DB_TRX_ID,DB_ROLL_PTR when the history is removed.
[TODO: It appears that the resetting is not taking place as often as
it could be. We should test that a simple INSERT should eventually
cause row_purge_reset_trx_id() to be invoked unless DROP TABLE is
invoked soon enough.]
The InnoDB clustered index record system columns DB_TRX_ID,DB_ROLL_PTR
are used by multi-versioning. After the history is no longer needed, these
columns can safely be reset to 0 and 1<<55 (to indicate a fresh insert).
When a reader sees 0 in the DB_TRX_ID column, it can instantly determine
that the record is present the read view. There is no need to acquire
the transaction system mutex to check if the transaction exists, because
writes can never be conducted by a transaction whose ID is 0.
The persistent InnoDB undo log used to be split into two parts:
insert_undo and update_undo. The insert_undo log was discarded at
transaction commit or rollback, and the update_undo log was processed
by the purge subsystem. As part of this change, we will only generate
a single undo log for new transactions, and the purge subsystem will
reset the DB_TRX_ID whenever a clustered index record is touched.
That is, all persistent undo log will be preserved at transaction commit
or rollback, to be removed by purge.
The InnoDB redo log format is changed in two ways:
We remove the redo log record type MLOG_UNDO_HDR_REUSE, and
we introduce the MLOG_ZIP_WRITE_TRX_ID record for updating the
DB_TRX_ID,DB_ROLL_PTR in a ROW_FORMAT=COMPRESSED table.
This is also changing the format of persistent InnoDB data files:
undo log and clustered index leaf page records. It will still be
possible via import and export to exchange data files with earlier
versions of MariaDB. The change to clustered index leaf page records
is simple: we allow DB_TRX_ID to be 0.
When it comes to the undo log, we must be able to upgrade from earlier
MariaDB versions after a clean shutdown (no redo log to apply).
While it would be nice to perform a slow shutdown (innodb_fast_shutdown=0)
before an upgrade, to empty the undo logs, we cannot assume that this
has been done. So, separate insert_undo log may exist for recovered
uncommitted transactions. These transactions may be automatically
rolled back, or they may be in XA PREPARE state, in which case InnoDB
will preserve the transaction until an explicit XA COMMIT or XA ROLLBACK.
Upgrade has been tested by starting up MariaDB 10.2 with
./mysql-test-run --manual-gdb innodb.read_only_recovery
and then starting up this patched server with
and without --innodb-read-only.
trx_undo_ptr_t::undo: Renamed from update_undo.
trx_undo_ptr_t::old_insert: Renamed from insert_undo.
trx_rseg_t::undo_list: Renamed from update_undo_list.
trx_rseg_t::undo_cached: Merged from update_undo_cached
and insert_undo_cached.
trx_rseg_t::old_insert_list: Renamed from insert_undo_list.
row_purge_reset_trx_id(): New function to reset the columns.
This will be called for all undo processing in purge
that does not remove the clustered index record.
trx_undo_update_rec_get_update(): Allow trx_id=0 when copying the
old DB_TRX_ID of the record to the undo log.
ReadView::changes_visible(): Allow id==0. (Return true for it.
This is what speeds up the MVCC.)
row_vers_impl_x_locked_low(), row_vers_build_for_semi_consistent_read():
Implement a fast path for DB_TRX_ID=0.
Always initialize the TRX_UNDO_PAGE_TYPE to 0. Remove undo->type.
MLOG_UNDO_HDR_REUSE: Remove. This changes the redo log format!
innobase_start_or_create_for_mysql(): Set srv_undo_sources before
starting any transactions.
The parsing of the MLOG_ZIP_WRITE_TRX_ID record was successfully
tested by running the following:
./mtr --parallel=auto --mysqld=--debug=d,ib_log innodb_zip.bug56680
grep MLOG_ZIP_WRITE_TRX_ID var/*/log/mysqld.1.err
2017-07-07 13:08:16 +03:00
|
|
|
|
|
|
|
if (srv_force_recovery < SRV_FORCE_NO_BACKGROUND) {
|
|
|
|
srv_undo_sources = true;
|
2019-10-29 22:37:12 +01:00
|
|
|
/* Create the dict stats gathering task */
|
|
|
|
dict_stats_start();
|
MDEV-12288 Reset DB_TRX_ID when the history is removed, to speed up MVCC
Let InnoDB purge reset DB_TRX_ID,DB_ROLL_PTR when the history is removed.
[TODO: It appears that the resetting is not taking place as often as
it could be. We should test that a simple INSERT should eventually
cause row_purge_reset_trx_id() to be invoked unless DROP TABLE is
invoked soon enough.]
The InnoDB clustered index record system columns DB_TRX_ID,DB_ROLL_PTR
are used by multi-versioning. After the history is no longer needed, these
columns can safely be reset to 0 and 1<<55 (to indicate a fresh insert).
When a reader sees 0 in the DB_TRX_ID column, it can instantly determine
that the record is present the read view. There is no need to acquire
the transaction system mutex to check if the transaction exists, because
writes can never be conducted by a transaction whose ID is 0.
The persistent InnoDB undo log used to be split into two parts:
insert_undo and update_undo. The insert_undo log was discarded at
transaction commit or rollback, and the update_undo log was processed
by the purge subsystem. As part of this change, we will only generate
a single undo log for new transactions, and the purge subsystem will
reset the DB_TRX_ID whenever a clustered index record is touched.
That is, all persistent undo log will be preserved at transaction commit
or rollback, to be removed by purge.
The InnoDB redo log format is changed in two ways:
We remove the redo log record type MLOG_UNDO_HDR_REUSE, and
we introduce the MLOG_ZIP_WRITE_TRX_ID record for updating the
DB_TRX_ID,DB_ROLL_PTR in a ROW_FORMAT=COMPRESSED table.
This is also changing the format of persistent InnoDB data files:
undo log and clustered index leaf page records. It will still be
possible via import and export to exchange data files with earlier
versions of MariaDB. The change to clustered index leaf page records
is simple: we allow DB_TRX_ID to be 0.
When it comes to the undo log, we must be able to upgrade from earlier
MariaDB versions after a clean shutdown (no redo log to apply).
While it would be nice to perform a slow shutdown (innodb_fast_shutdown=0)
before an upgrade, to empty the undo logs, we cannot assume that this
has been done. So, separate insert_undo log may exist for recovered
uncommitted transactions. These transactions may be automatically
rolled back, or they may be in XA PREPARE state, in which case InnoDB
will preserve the transaction until an explicit XA COMMIT or XA ROLLBACK.
Upgrade has been tested by starting up MariaDB 10.2 with
./mysql-test-run --manual-gdb innodb.read_only_recovery
and then starting up this patched server with
and without --innodb-read-only.
trx_undo_ptr_t::undo: Renamed from update_undo.
trx_undo_ptr_t::old_insert: Renamed from insert_undo.
trx_rseg_t::undo_list: Renamed from update_undo_list.
trx_rseg_t::undo_cached: Merged from update_undo_cached
and insert_undo_cached.
trx_rseg_t::old_insert_list: Renamed from insert_undo_list.
row_purge_reset_trx_id(): New function to reset the columns.
This will be called for all undo processing in purge
that does not remove the clustered index record.
trx_undo_update_rec_get_update(): Allow trx_id=0 when copying the
old DB_TRX_ID of the record to the undo log.
ReadView::changes_visible(): Allow id==0. (Return true for it.
This is what speeds up the MVCC.)
row_vers_impl_x_locked_low(), row_vers_build_for_semi_consistent_read():
Implement a fast path for DB_TRX_ID=0.
Always initialize the TRX_UNDO_PAGE_TYPE to 0. Remove undo->type.
MLOG_UNDO_HDR_REUSE: Remove. This changes the redo log format!
innobase_start_or_create_for_mysql(): Set srv_undo_sources before
starting any transactions.
The parsing of the MLOG_ZIP_WRITE_TRX_ID record was successfully
tested by running the following:
./mtr --parallel=auto --mysqld=--debug=d,ib_log innodb_zip.bug56680
grep MLOG_ZIP_WRITE_TRX_ID var/*/log/mysqld.1.err
2017-07-07 13:08:16 +03:00
|
|
|
/* Create the thread that will optimize the
|
|
|
|
FULLTEXT search index subsystem. */
|
|
|
|
fts_optimize_init();
|
|
|
|
}
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2021-05-20 14:58:25 +03:00
|
|
|
err = dict_sys.create_or_check_sys_tables();
|
2017-02-01 15:47:33 +02:00
|
|
|
switch (err) {
|
|
|
|
case DB_SUCCESS:
|
|
|
|
break;
|
|
|
|
case DB_READ_ONLY:
|
|
|
|
if (srv_force_recovery >= SRV_FORCE_NO_TRX_UNDO) {
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
ib::error() << "Cannot create system tables in read-only mode";
|
|
|
|
/* fall through */
|
|
|
|
default:
|
2016-08-12 11:17:45 +03:00
|
|
|
return(srv_init_abort(err));
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2023-03-23 16:26:17 +03:00
|
|
|
if (!srv_read_only_mode
|
|
|
|
&& srv_operation <= SRV_OPERATION_EXPORT_RESTORED) {
|
2017-05-10 15:13:11 +03:00
|
|
|
/* Initialize the innodb_temporary tablespace and keep
|
|
|
|
it open until shutdown. */
|
|
|
|
err = srv_open_tmp_tablespace(create_new_db);
|
|
|
|
|
|
|
|
if (err != DB_SUCCESS) {
|
|
|
|
return(srv_init_abort(err));
|
|
|
|
}
|
|
|
|
|
2018-05-09 16:52:45 +03:00
|
|
|
if (srv_force_recovery < SRV_FORCE_NO_BACKGROUND) {
|
2019-10-29 22:37:12 +01:00
|
|
|
srv_start_periodic_timer(srv_master_timer, srv_master_callback, 1000);
|
2018-05-09 16:52:45 +03:00
|
|
|
}
|
2017-06-21 12:22:02 +03:00
|
|
|
}
|
MDEV-13039 innodb_fast_shutdown=0 may fail to purge all undo log
When a slow shutdown is performed soon after spawning some work for
background threads that can create or commit transactions, it is possible
that new transactions are started or committed after the purge has finished.
This is violating the specification of innodb_fast_shutdown=0, namely that
the purge must be completed. (None of the history of the recent transactions
would be purged.)
Also, it is possible that the purge threads would exit in slow shutdown
while there exist active transactions, such as recovered incomplete
transactions that are being rolled back. Thus, the slow shutdown could
fail to purge some undo log that becomes purgeable after the transaction
commit or rollback.
srv_undo_sources: A flag that indicates if undo log can be generated
or the persistent, whether by background threads or by user SQL.
Even when this flag is clear, active transactions that already exist
in the system may be committed or rolled back.
innodb_shutdown(): Renamed from innobase_shutdown_for_mysql().
Do not return an error code; the operation never fails.
Clear the srv_undo_sources flag, and also ensure that the background
DROP TABLE queue is empty.
srv_purge_should_exit(): Do not allow the purge to exit if
srv_undo_sources are active or the background DROP TABLE queue is not
empty, or in slow shutdown, if any active transactions exist
(and are being rolled back).
srv_purge_coordinator_thread(): Remove some previous workarounds
for this bug.
innobase_start_or_create_for_mysql(): Set buf_page_cleaner_is_active
and srv_dict_stats_thread_active directly. Set srv_undo_sources before
starting the purge subsystem, to prevent immediate shutdown of the purge.
Create dict_stats_thread and fts_optimize_thread immediately
after setting srv_undo_sources, so that shutdown can use this flag to
determine if these subsystems were started.
dict_stats_shutdown(): Shut down dict_stats_thread. Backported from 10.2.
srv_shutdown_table_bg_threads(): Remove (unused).
2017-06-08 15:43:06 +03:00
|
|
|
|
2017-12-13 23:14:15 +02:00
|
|
|
srv_is_being_started = false;
|
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
if (srv_print_verbose_log) {
|
MDEV-14425 Improve the redo log for concurrency
The InnoDB redo log used to be formatted in blocks of 512 bytes.
The log blocks were encrypted and the checksum was calculated while
holding log_sys.mutex, creating a serious scalability bottleneck.
We remove the fixed-size redo log block structure altogether and
essentially turn every mini-transaction into a log block of its own.
This allows encryption and checksum calculations to be performed
on local mtr_t::m_log buffers, before acquiring log_sys.mutex.
The mutex only protects a memcpy() of the data to the shared
log_sys.buf, as well as the padding of the log, in case the
to-be-written part of the log would not end in a block boundary of
the underlying storage. For now, the "padding" consists of writing
a single NUL byte, to allow recovery and mariadb-backup to detect
the end of the circular log faster.
Like the previous implementation, we will overwrite the last log block
over and over again, until it has been completely filled. It would be
possible to write only up to the last completed block (if no more
recent write was requested), or to write dummy FILE_CHECKPOINT records
to fill the incomplete block, by invoking the currently disabled
function log_pad(). This would require adjustments to some logic around
log checkpoints, page flushing, and shutdown.
An upgrade after a crash of any previous version is not supported.
Logically empty log files from a previous version will be upgraded.
An attempt to start up InnoDB without a valid ib_logfile0 will be
refused. Previously, the redo log used to be created automatically
if it was missing. Only with with innodb_force_recovery=6, it is
possible to start InnoDB in read-only mode even if the log file
does not exist. This allows the contents of a possibly corrupted
database to be dumped.
Because a prepared backup from an earlier version of mariadb-backup
will create a 0-sized log file, we will allow an upgrade from such
log files, provided that the FIL_PAGE_FILE_FLUSH_LSN in the system
tablespace looks valid.
The 512-byte log checkpoint blocks at 0x200 and 0x600 will be replaced
with 64-byte log checkpoint blocks at 0x1000 and 0x2000.
The start of log records will move from 0x800 to 0x3000. This allows us
to use 4096-byte aligned blocks for all I/O in a future revision.
We extend the MDEV-12353 redo log record format as follows.
(1) Empty mini-transactions or extra NUL bytes will not be allowed.
(2) The end-of-minitransaction marker (a NUL byte) will be replaced
with a 1-bit sequence number, which will be toggled each time when the
circular log file wraps back to the beginning.
(3) After the sequence bit, a CRC-32C checksum of all data
(excluding the sequence bit) will written.
(4) If the log is encrypted, 8 bytes will be written before
the checksum and included in it. This is part of the
initialization vector (IV) of encrypted log data.
(5) File names, page numbers, and checkpoint information will not be
encrypted. Only the payload bytes of page-level log will be encrypted.
The tablespace ID and page number will form part of the IV.
(6) For padding, arbitrary-length FILE_CHECKPOINT records may be written,
with all-zero payload, and with the normal end marker and checksum.
The minimum size is 7 bytes, or 7+8 with innodb_encrypt_log=ON.
In mariadb-backup and in Galera snapshot transfer (SST) scripts, we will
no longer remove ib_logfile0 or create an empty ib_logfile0. Server startup
will require a valid log file. When resizing the log, we will create
a logically empty ib_logfile101 at the current LSN and use an atomic rename
to replace ib_logfile0 with it. See the test innodb.log_file_size.
Because there is no mandatory padding in the log file, we are able
to create a dummy log file as of an arbitrary log sequence number.
See the test mariabackup.huge_lsn.
The parameter innodb_log_write_ahead_size and the
INFORMATION_SCHEMA.INNODB_METRICS counter log_padded will be removed.
The minimum value of innodb_log_buffer_size will be increased to 2MiB
(because log_sys.buf will replace recv_sys.buf) and the increment
adjusted to 4096 bytes (the maximum log block size).
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be removed:
os_log_fsyncs
os_log_pending_fsyncs
log_pending_log_flushes
log_pending_checkpoint_writes
The following status variables will be removed:
Innodb_os_log_fsyncs (this is included in Innodb_data_fsyncs)
Innodb_os_log_pending_fsyncs (this was limited to at most 1 by design)
log_sys.get_block_size(): Return the physical block size of the log file.
This is only implemented on Linux and Microsoft Windows for now, and for
the power-of-2 block sizes between 64 and 4096 bytes (the minimum and
maximum size of a checkpoint block). If the block size is anything else,
the traditional 512-byte size will be used via normal file system
buffering.
If the file system buffers can be bypassed, a message like the following
will be issued:
InnoDB: File system buffers for log disabled (block size=512 bytes)
InnoDB: File system buffers for log disabled (block size=4096 bytes)
This has been tested on Linux and Microsoft Windows with both sizes.
On Linux, only enable O_DIRECT on the log for innodb_flush_method=O_DSYNC.
Tests in 3 different environments where the log is stored in a device
with a physical block size of 512 bytes are yielding better throughput
without O_DIRECT. This could be due to the fact that in the event the
last log block is being overwritten (if multiple transactions would
become durable at the same time, and each of will write a small
number of bytes to the last log block), it should be faster to re-copy
data from log_sys.buf or log_sys.flush_buf to the kernel buffer,
to be finally written at fdatasync() time.
The parameter innodb_flush_method=O_DSYNC will imply O_DIRECT for
data files. This option will enable O_DIRECT on the log file on Linux.
It may be unsafe to use when the storage device does not support
FUA (Force Unit Access) mode.
When the server is compiled WITH_PMEM=ON, we will use memory-mapped
I/O for the log file if the log resides on a "mount -o dax" device.
We will identify PMEM in a start-up message:
InnoDB: log sequence number 0 (memory-mapped); transaction id 3
On Linux, we will also invoke mmap() on any ib_logfile0 that resides
in /dev/shm, effectively treating the log file as persistent memory.
This should speed up "./mtr --mem" and increase the test coverage of
PMEM on non-PMEM hardware. It also allows users to estimate how much
the performance would be improved by installing persistent memory.
On other tmpfs file systems such as /run, we will not use mmap().
mariadb-backup: Eliminated several variables. We will refer
directly to recv_sys and log_sys.
backup_wait_for_lsn(): Detect non-progress of
xtrabackup_copy_logfile(). In this new log format with
arbitrary-sized blocks, we can only detect log file overrun
indirectly, by observing that the scanned log sequence number
is not advancing.
xtrabackup_copy_logfile(): On PMEM, do not modify the sequence bit,
because we are not allowed to modify the server's log file, and our
memory mapping is read-only.
trx_flush_log_if_needed_low(): Do not use the callback on pmem.
Using neither flush_lock nor write_lock around PMEM writes seems
to yield the best performance. The pmem_persist() calls may
still be somewhat slower than the pwrite() and fdatasync() based
interface (PMEM mounted without -o dax).
recv_sys_t::buf: Remove. We will use log_sys.buf for parsing.
recv_sys_t::MTR_SIZE_MAX: Replaces RECV_SCAN_SIZE.
recv_sys_t::file_checkpoint: Renamed from mlog_checkpoint_lsn.
recv_sys_t, log_sys_t: Removed many data members.
recv_sys.lsn: Renamed from recv_sys.recovered_lsn.
recv_sys.offset: Renamed from recv_sys.recovered_offset.
log_sys.buf_size: Replaces srv_log_buffer_size.
recv_buf: A smart pointer that wraps log_sys.buf[recv_sys.offset]
when the buffer is being allocated from the memory heap.
recv_ring: A smart pointer that wraps a circular log_sys.buf[] that is
backed by ib_logfile0. The pointer will wrap from recv_sys.len
(log_sys.file_size) to log_sys.START_OFFSET. For the record that
wraps around, we may copy file name or record payload data to
the auxiliary buffer decrypt_buf in order to have a contiguous
block of memory. The maximum size of a record is less than
innodb_page_size bytes.
recv_sys_t::parse(): Take the smart pointer as a template parameter.
Do not temporarily add a trailing NUL byte to FILE_ records, because
we are not supposed to modify the memory-mapped log file. (It is
attached in read-write mode already during recovery.)
recv_sys_t::parse_mtr(): Wrapper for recv_sys_t::parse().
recv_sys_t::parse_pmem(): Like parse_mtr(), but if PREMATURE_EOF would be
returned on PMEM, use recv_ring to wrap around the buffer to the start.
mtr_t::finish_write(), log_close(): Do not enforce log_sys.max_buf_free
on PMEM, because it has no meaning on the mmap-based log.
log_sys.write_to_buf: Count writes to log_sys.buf. Replaces
srv_stats.log_write_requests and export_vars.innodb_log_write_requests.
Protected by log_sys.mutex. Updated consistently in log_close().
Previously, mtr_t::commit() conditionally updated the count,
which was inconsistent.
log_sys.write_to_log: Count swaps of log_sys.buf and log_sys.flush_buf,
for writing to log_sys.log (the ib_logfile0). Replaces
srv_stats.log_writes and export_vars.innodb_log_writes.
Protected by log_sys.mutex.
log_sys.waits: Count waits in append_prepare(). Replaces
srv_stats.log_waits and export_vars.innodb_log_waits.
recv_recover_page(): Do not unnecessarily acquire
log_sys.flush_order_mutex. We are inserting the blocks in arbitary
order anyway, to be adjusted in recv_sys.apply(true).
We will change the definition of flush_lock and write_lock to
avoid potential false sharing. Depending on sizeof(log_sys) and
CPU_LEVEL1_DCACHE_LINESIZE, the flush_lock and write_lock could
share a cache line with each other or with the last data members
of log_sys.
Thanks to Matthias Leich for providing https://rr-project.org traces
for various failures during the development, and to
Thirunarayanan Balathandayuthapani for his help in debugging
some of the recovery code. And thanks to the developers of the
rr debugger for a tool without which extensive changes to InnoDB
would be very challenging to get right.
Thanks to Vladislav Vaintroub for useful feedback and
to him, Axel Schwenke and Krunal Bauskar for testing the performance.
2022-01-21 16:03:47 +02:00
|
|
|
sql_print_information("InnoDB: "
|
|
|
|
"log sequence number " LSN_PF
|
|
|
|
#ifdef HAVE_PMEM
|
|
|
|
"%s"
|
|
|
|
#endif
|
|
|
|
"; transaction id " TRX_ID_FMT,
|
|
|
|
recv_sys.lsn,
|
|
|
|
#ifdef HAVE_PMEM
|
|
|
|
log_sys.is_pmem()
|
|
|
|
? " (memory-mapped)" : "",
|
|
|
|
#endif
|
|
|
|
trx_sys.get_max_trx_id());
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
if (!srv_read_only_mode) {
|
2016-08-12 11:17:45 +03:00
|
|
|
if (create_new_db) {
|
|
|
|
srv_buffer_pool_load_at_startup = FALSE;
|
|
|
|
}
|
|
|
|
|
2015-07-14 16:05:29 -04:00
|
|
|
#ifdef WITH_WSREP
|
|
|
|
/*
|
|
|
|
Create the dump/load thread only when not running with
|
|
|
|
--wsrep-recover.
|
|
|
|
*/
|
2019-01-23 15:30:00 +04:00
|
|
|
if (!get_wsrep_recovery()) {
|
2015-07-14 16:05:29 -04:00
|
|
|
#endif /* WITH_WSREP */
|
2017-08-31 08:27:59 +03:00
|
|
|
|
2019-10-29 22:37:12 +01:00
|
|
|
/* Start buffer pool dump/load task */
|
|
|
|
buf_load_at_startup();
|
MDEV-11638 Encryption causes race conditions in InnoDB shutdown
InnoDB shutdown failed to properly take fil_crypt_thread() into account.
The encryption threads were signalled to shut down together with other
non-critical tasks. This could be much too early in case of slow shutdown,
which could need minutes to complete the purge. Furthermore, InnoDB
failed to wait for the fil_crypt_thread() to actually exit before
proceeding to the final steps of shutdown, causing the race conditions.
Furthermore, the log_scrub_thread() was shut down way too early.
Also it should remain until the SRV_SHUTDOWN_FLUSH_PHASE.
fil_crypt_threads_end(): Remove. This would cause the threads to
be terminated way too early.
srv_buf_dump_thread_active, srv_dict_stats_thread_active,
lock_sys->timeout_thread_active, log_scrub_thread_active,
srv_monitor_active, srv_error_monitor_active: Remove a race condition
between startup and shutdown, by setting these in the startup thread
that creates threads, not in each created thread. In this way, once the
flag is cleared, it will remain cleared during shutdown.
srv_n_fil_crypt_threads_started, fil_crypt_threads_event: Declare in
global rather than static scope.
log_scrub_event, srv_log_scrub_thread_active, log_scrub_thread():
Declare in static rather than global scope. Let these be created by
log_init() and freed by log_shutdown().
rotate_thread_t::should_shutdown(): Do not shut down before the
SRV_SHUTDOWN_FLUSH_PHASE.
srv_any_background_threads_are_active(): Remove. These checks now
exist in logs_empty_and_mark_files_at_shutdown().
logs_empty_and_mark_files_at_shutdown(): Shut down the threads in
the proper order. Keep fil_crypt_thread() and log_scrub_thread() alive
until SRV_SHUTDOWN_FLUSH_PHASE, and check that they actually terminate.
2017-01-04 18:43:32 +02:00
|
|
|
|
2015-07-14 16:05:29 -04:00
|
|
|
#ifdef WITH_WSREP
|
|
|
|
} else {
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::warn() <<
|
2015-07-14 16:05:29 -04:00
|
|
|
"Skipping buffer pool dump/restore during "
|
2016-08-12 11:17:45 +03:00
|
|
|
"wsrep recovery.";
|
2015-07-14 16:05:29 -04:00
|
|
|
}
|
|
|
|
#endif /* WITH_WSREP */
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2017-01-31 19:43:03 +02:00
|
|
|
/* Create thread(s) that handles key rotation. This is
|
|
|
|
needed already here as log_preflush_pool_modified_pages
|
|
|
|
will flush dirty pages and that might need e.g.
|
2020-12-04 16:18:04 +02:00
|
|
|
fil_crypt_threads_cond. */
|
2017-01-31 19:43:03 +02:00
|
|
|
fil_crypt_threads_init();
|
|
|
|
|
|
|
|
/* Initialize online defragmentation. */
|
|
|
|
btr_defragment_init();
|
|
|
|
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
srv_started_redo = true;
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
return(DB_SUCCESS);
|
|
|
|
}
|
|
|
|
|
2019-10-29 22:37:12 +01:00
|
|
|
/**
|
2019-11-13 18:14:44 +01:00
|
|
|
Shutdown purge to make sure that there is no possibility that we call any
|
|
|
|
plugin code (e.g., audit) inside virtual column computation.
|
2019-10-29 22:37:12 +01:00
|
|
|
*/
|
|
|
|
void innodb_preshutdown()
|
|
|
|
{
|
2019-11-13 18:14:44 +01:00
|
|
|
static bool first_time= true;
|
|
|
|
if (!first_time)
|
|
|
|
return;
|
|
|
|
first_time= false;
|
|
|
|
|
|
|
|
if (srv_read_only_mode)
|
|
|
|
return;
|
2023-03-31 21:32:41 +02:00
|
|
|
if (!srv_fast_shutdown && srv_operation <= SRV_OPERATION_EXPORT_RESTORED)
|
2023-11-14 14:35:51 +02:00
|
|
|
if (srv_force_recovery < SRV_FORCE_NO_TRX_UNDO && srv_was_started)
|
2020-10-09 12:47:58 +03:00
|
|
|
while (trx_sys.any_active_transactions())
|
2021-03-16 16:09:41 +03:00
|
|
|
std::this_thread::sleep_for(std::chrono::milliseconds(1));
|
2019-11-13 18:14:44 +01:00
|
|
|
srv_shutdown_bg_undo_sources();
|
|
|
|
srv_purge_shutdown();
|
2020-10-26 15:04:24 +02:00
|
|
|
|
|
|
|
if (srv_n_fil_crypt_threads)
|
|
|
|
fil_crypt_set_thread_cnt(0);
|
2019-10-29 22:37:12 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
|
2017-01-31 19:43:03 +02:00
|
|
|
/** Shut down InnoDB. */
|
2018-04-29 09:41:42 +03:00
|
|
|
void innodb_shutdown()
|
2014-02-26 19:11:54 +01:00
|
|
|
{
|
2019-10-29 22:37:12 +01:00
|
|
|
innodb_preshutdown();
|
2017-06-08 15:43:06 +03:00
|
|
|
ut_ad(!srv_undo_sources);
|
MDEV-12548 Initial implementation of Mariabackup for MariaDB 10.2
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
2017-06-30 10:49:37 +03:00
|
|
|
switch (srv_operation) {
|
|
|
|
case SRV_OPERATION_BACKUP:
|
Follow-up fix to MDEV-12988 backup fails if innodb_undo_tablespaces>0
The fix broke mariabackup --prepare --incremental.
The restore of an incremental backup starts up (parts of) InnoDB twice.
First, all data files are discovered for applying .delta files. Then,
after the .delta files have been applied, InnoDB will be restarted
more completely, so that the redo log records will be applied via the
buffer pool.
During the first startup, the buffer pool is not initialized, and thus
trx_rseg_get_n_undo_tablespaces() must not be invoked. The apply of
the .delta files will currently assume that the --innodb-undo-tablespaces
option correctly specifies the number of undo tablespace files, just
like --backup does.
The second InnoDB startup of --prepare for applying the redo log will
properly invoke trx_rseg_get_n_undo_tablespaces().
enum srv_operation_mode: Add SRV_OPERATION_RESTORE_DELTA for
distinguishing the apply of .delta files from SRV_OPERATION_RESTORE.
srv_undo_tablespaces_init(): In mariabackup --prepare --incremental,
in the initial SRV_OPERATION_RESTORE_DELTA phase, do not invoke
trx_rseg_get_n_undo_tablespaces() because the buffer pool or the
redo logs are not available. Instead, blindly rely on the parameter
--innodb-undo-tablespaces.
2017-08-18 08:52:41 +03:00
|
|
|
case SRV_OPERATION_RESTORE_DELTA:
|
2022-01-29 18:10:25 +05:30
|
|
|
case SRV_OPERATION_BACKUP_NO_DEFER:
|
2020-10-26 15:04:24 +02:00
|
|
|
break;
|
|
|
|
case SRV_OPERATION_RESTORE:
|
2017-10-10 10:28:54 +03:00
|
|
|
case SRV_OPERATION_RESTORE_EXPORT:
|
2020-10-26 15:04:24 +02:00
|
|
|
mysql_mutex_lock(&buf_pool.flush_list_mutex);
|
MDEV-27416 InnoDB hang in buf_flush_wait_flushed(), on log checkpoint
InnoDB could sometimes hang when triggering a log checkpoint. This is
due to commit 7b1252c03d7131754d9503560fe507b33ca1f8b4 (MDEV-24278),
which introduced an untimed wait to buf_flush_page_cleaner().
The hang was noticed by occasional failures of IMPORT TABLESPACE tests,
such as innodb.innodb-wl5522, which would (unnecessarily) invoke
log_make_checkpoint() from row_import_cleanup().
The reason of the hang was that buf_flush_page_cleaner() would enter
untimed sleep despite buf_flush_sync_lsn being set. The exact failure
scenario is unclear, because buf_flush_sync_lsn should actually be
protected by buf_pool.flush_list_mutex. We prevent the hang by
invoking buf_pool.page_cleaner_set_idle(false) whenever we are
setting buf_flush_sync_lsn and signaling buf_pool.do_flush_list.
The bulk of these changes was originally developed as a preparation
for MDEV-26827, to invoke buf_flush_list() from fewer threads,
and tested on 10.6 by Matthias Leich.
This fix was tested by running 100 repetitions of 100 concurrent instances
of the test innodb.innodb-wl5522 on a RelWithDebInfo build, using ext4fs
and innodb_flush_method=O_DIRECT on a SATA SSD with 4096-byte block size.
During the test, the call to log_make_checkpoint() in row_import_cleanup()
was present.
buf_flush_list(): Make static.
buf_flush_wait(): Wait for buf_pool.get_oldest_modification()
to reach a target, by work done in the buf_flush_page_cleaner.
If buf_flush_sync_lsn is going to be set, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_ahead(): If buf_flush_sync_lsn or buf_flush_async_lsn
is going to be set and the page cleaner woken up, we will invoke
buf_pool.page_cleaner_set_idle(false).
buf_flush_wait_flushed(): Invoke buf_flush_wait().
buf_flush_sync(): Invoke recv_sys.apply() at the start in case
crash recovery is active. Invoke buf_flush_wait().
buf_flush_sync_batch(): A lower-level variant of buf_flush_sync()
that is only called by recv_sys_t::apply().
buf_flush_sync_for_checkpoint(): Do not trigger log apply
or checkpoint during recovery.
buf_dblwr_t::create(): Only initiate a buffer pool flush, not
a checkpoint.
row_import_cleanup(): Do not unnecessarily invoke log_make_checkpoint().
Invoking buf_flush_list_space() before starting to generate redo log
for the imported tablespace should suffice.
srv_prepare_to_delete_redo_log_file():
Set recv_sys.recovery_on in order to prevent
buf_flush_sync_for_checkpoint() from initiating a checkpoint
while the log is inaccessible. Remove a wait loop that is already
part of buf_flush_sync().
Do not invoke fil_names_clear() if the log is being upgraded,
because the FILE_MODIFY record is specific to the latest format.
create_log_file(): Clear recv_sys.recovery_on only after calling
log_make_checkpoint(), to prevent buf_flush_page_cleaner from
invoking a checkpoint.
innodb_shutdown(): Simplify the logic in mariadb-backup --prepare.
os_aio_wait_until_no_pending_writes(): Update the function comment.
Apart from row_quiesce_table_start() during FLUSH TABLES...FOR EXPORT,
this is being called by buf_flush_list_space(), which is invoked
by ALTER TABLE...IMPORT TABLESPACE as well as some encryption operations.
2022-01-04 07:40:31 +02:00
|
|
|
srv_shutdown_state = SRV_SHUTDOWN_CLEANUP;
|
2020-10-26 15:04:24 +02:00
|
|
|
while (buf_page_cleaner_is_active) {
|
2021-02-07 12:19:24 +02:00
|
|
|
pthread_cond_signal(&buf_pool.do_flush_list);
|
|
|
|
my_cond_wait(&buf_pool.done_flush_list,
|
|
|
|
&buf_pool.flush_list_mutex.m_mutex);
|
2020-10-26 15:04:24 +02:00
|
|
|
}
|
|
|
|
mysql_mutex_unlock(&buf_pool.flush_list_mutex);
|
MDEV-12548 Initial implementation of Mariabackup for MariaDB 10.2
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
2017-06-30 10:49:37 +03:00
|
|
|
break;
|
|
|
|
case SRV_OPERATION_NORMAL:
|
2023-03-23 16:26:17 +03:00
|
|
|
case SRV_OPERATION_EXPORT_RESTORED:
|
MDEV-12548 Initial implementation of Mariabackup for MariaDB 10.2
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
2017-06-30 10:49:37 +03:00
|
|
|
/* Shut down the persistent files. */
|
|
|
|
logs_empty_and_mark_files_at_shutdown();
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
MDEV-15053 Reduce buf_pool_t::mutex contention
User-visible changes: The INFORMATION_SCHEMA views INNODB_BUFFER_PAGE
and INNODB_BUFFER_PAGE_LRU will report a dummy value FLUSH_TYPE=0
and will no longer report the PAGE_STATE value READY_FOR_USE.
We will remove some fields from buf_page_t and move much code to
member functions of buf_pool_t and buf_page_t, so that the access
rules of data members can be enforced consistently.
Evicting or adding pages in buf_pool.LRU will remain covered by
buf_pool.mutex.
Evicting or adding pages in buf_pool.page_hash will remain
covered by both buf_pool.mutex and the buf_pool.page_hash X-latch.
After this fix, buf_pool.page_hash lookups can entirely
avoid acquiring buf_pool.mutex, only relying on
buf_pool.hash_lock_get() S-latch.
Similarly, buf_flush_check_neighbors() can will rely solely on
buf_pool.mutex, no buf_pool.page_hash latch at all.
The buf_pool.mutex is rather contended in I/O heavy benchmarks,
especially when the workload does not fit in the buffer pool.
The first attempt to alleviate the contention was the
buf_pool_t::mutex split in
commit 4ed7082eefe56b3e97e0edefb3df76dd7ef5e858
which introduced buf_block_t::mutex, which we are now removing.
Later, multiple instances of buf_pool_t were introduced
in commit c18084f71b02ea707c6461353e6cfc15d7553bc6
and recently removed by us in
commit 1a6f708ec594ac0ae2dd30db926ab07b100fa24b (MDEV-15058).
UNIV_BUF_DEBUG: Remove. This option to enable some buffer pool
related debugging in otherwise non-debug builds has not been used
for years. Instead, we have been using UNIV_DEBUG, which is enabled
in CMAKE_BUILD_TYPE=Debug.
buf_block_t::mutex, buf_pool_t::zip_mutex: Remove. We can mainly rely on
std::atomic and the buf_pool.page_hash latches, and in some cases
depend on buf_pool.mutex or buf_pool.flush_list_mutex just like before.
We must always release buf_block_t::lock before invoking
unfix() or io_unfix(), to prevent a glitch where a block that was
added to the buf_pool.free list would apper X-latched. See
commit c5883debd6ef440a037011c11873b396923e93c5 how this glitch
was finally caught in a debug environment.
We move some buf_pool_t::page_hash specific code from the
ha and hash modules to buf_pool, for improved readability.
buf_pool_t::close(): Assert that all blocks are clean, except
on aborted startup or crash-like shutdown.
buf_pool_t::validate(): No longer attempt to validate
n_flush[] against the number of BUF_IO_WRITE fixed blocks,
because buf_page_t::flush_type no longer exists.
buf_pool_t::watch_set(): Replaces buf_pool_watch_set().
Reduce mutex contention by separating the buf_pool.watch[]
allocation and the insert into buf_pool.page_hash.
buf_pool_t::page_hash_lock<bool exclusive>(): Acquire a
buf_pool.page_hash latch.
Replaces and extends buf_page_hash_lock_s_confirm()
and buf_page_hash_lock_x_confirm().
buf_pool_t::READ_AHEAD_PAGES: Renamed from BUF_READ_AHEAD_PAGES.
buf_pool_t::curr_size, old_size, read_ahead_area, n_pend_reads:
Use Atomic_counter.
buf_pool_t::running_out(): Replaces buf_LRU_buf_pool_running_out().
buf_pool_t::LRU_remove(): Remove a block from the LRU list
and return its predecessor. Incorporates buf_LRU_adjust_hp(),
which was removed.
buf_page_get_gen(): Remove a redundant call of fsp_is_system_temporary(),
for mode == BUF_GET_IF_IN_POOL_OR_WATCH, which is only used by
BTR_DELETE_OP (purge), which is never invoked on temporary tables.
buf_free_from_unzip_LRU_list_batch(): Avoid redundant assignments.
buf_LRU_free_from_unzip_LRU_list(): Simplify the loop condition.
buf_LRU_free_page(): Clarify the function comment.
buf_flush_check_neighbor(), buf_flush_check_neighbors():
Rewrite the construction of the page hash range. We will hold
the buf_pool.mutex for up to buf_pool.read_ahead_area (at most 64)
consecutive lookups of buf_pool.page_hash.
buf_flush_page_and_try_neighbors(): Remove.
Merge to its only callers, and remove redundant operations in
buf_flush_LRU_list_batch().
buf_read_ahead_random(), buf_read_ahead_linear(): Rewrite.
Do not acquire buf_pool.mutex, and iterate directly with page_id_t.
ut_2_power_up(): Remove. my_round_up_to_next_power() is inlined
and avoids any loops.
fil_page_get_prev(), fil_page_get_next(), fil_addr_is_null(): Remove.
buf_flush_page(): Add a fil_space_t* parameter. Minimize the
buf_pool.mutex hold time. buf_pool.n_flush[] is no longer updated
atomically with the io_fix, and we will protect most buf_block_t
fields with buf_block_t::lock. The function
buf_flush_write_block_low() is removed and merged here.
buf_page_init_for_read(): Use static linkage. Initialize the newly
allocated block and acquire the exclusive buf_block_t::lock while not
holding any mutex.
IORequest::IORequest(): Remove the body. We only need to invoke
set_punch_hole() in buf_flush_page() and nowhere else.
buf_page_t::flush_type: Remove. Replaced by IORequest::flush_type.
This field is only used during a fil_io() call.
That function already takes IORequest as a parameter, so we had
better introduce for the rarely changing field.
buf_block_t::init(): Replaces buf_page_init().
buf_page_t::init(): Replaces buf_page_init_low().
buf_block_t::initialise(): Initialise many fields, but
keep the buf_page_t::state(). Both buf_pool_t::validate() and
buf_page_optimistic_get() requires that buf_page_t::in_file()
be protected atomically with buf_page_t::in_page_hash
and buf_page_t::in_LRU_list.
buf_page_optimistic_get(): Now that buf_block_t::mutex
no longer exists, we must check buf_page_t::io_fix()
after acquiring the buf_pool.page_hash lock, to detect
whether buf_page_init_for_read() has been initiated.
We will also check the io_fix() before acquiring hash_lock
in order to avoid unnecessary computation.
The field buf_block_t::modify_clock (protected by buf_block_t::lock)
allows buf_page_optimistic_get() to validate the block.
buf_page_t::real_size: Remove. It was only used while flushing
pages of page_compressed tables.
buf_page_encrypt(): Add an output parameter that allows us ot eliminate
buf_page_t::real_size. Replace a condition with debug assertion.
buf_page_should_punch_hole(): Remove.
buf_dblwr_t::add_to_batch(): Replaces buf_dblwr_add_to_batch().
Add the parameter size (to replace buf_page_t::real_size).
buf_dblwr_t::write_single_page(): Replaces buf_dblwr_write_single_page().
Add the parameter size (to replace buf_page_t::real_size).
fil_system_t::detach(): Replaces fil_space_detach().
Ensure that fil_validate() will not be violated even if
fil_system.mutex is released and reacquired.
fil_node_t::complete_io(): Renamed from fil_node_complete_io().
fil_node_t::close_to_free(): Replaces fil_node_close_to_free().
Avoid invoking fil_node_t::close() because fil_system.n_open
has already been decremented in fil_space_t::detach().
BUF_BLOCK_READY_FOR_USE: Remove. Directly use BUF_BLOCK_MEMORY.
BUF_BLOCK_ZIP_DIRTY: Remove. Directly use BUF_BLOCK_ZIP_PAGE,
and distinguish dirty pages by buf_page_t::oldest_modification().
BUF_BLOCK_POOL_WATCH: Remove. Use BUF_BLOCK_NOT_USED instead.
This state was only being used for buf_page_t that are in
buf_pool.watch.
buf_pool_t::watch[]: Remove pointer indirection.
buf_page_t::in_flush_list: Remove. It was set if and only if
buf_page_t::oldest_modification() is nonzero.
buf_page_decrypt_after_read(), buf_corrupt_page_release(),
buf_page_check_corrupt(): Change the const fil_space_t* parameter
to const fil_node_t& so that we can report the correct file name.
buf_page_monitor(): Declare as an ATTRIBUTE_COLD global function.
buf_page_io_complete(): Split to buf_page_read_complete() and
buf_page_write_complete().
buf_dblwr_t::in_use: Remove.
buf_dblwr_t::buf_block_array: Add IORequest::flush_t.
buf_dblwr_sync_datafiles(): Remove. It was a useless wrapper of
os_aio_wait_until_no_pending_writes().
buf_flush_write_complete(): Declare static, not global.
Add the parameter IORequest::flush_t.
buf_flush_freed_page(): Simplify the code.
recv_sys_t::flush_lru: Renamed from flush_type and changed to bool.
fil_read(), fil_write(): Replaced with direct use of fil_io().
fil_buffering_disabled(): Remove. Check srv_file_flush_method directly.
fil_mutex_enter_and_prepare_for_io(): Return the resolved
fil_space_t* to avoid a duplicated lookup in the caller.
fil_report_invalid_page_access(): Clean up the parameters.
fil_io(): Return fil_io_t, which comprises fil_node_t and error code.
Always invoke fil_space_t::acquire_for_io() and let either the
sync=true caller or fil_aio_callback() invoke
fil_space_t::release_for_io().
fil_aio_callback(): Rewrite to replace buf_page_io_complete().
fil_check_pending_operations(): Remove a parameter, and remove some
redundant lookups.
fil_node_close_to_free(): Wait for n_pending==0. Because we no longer
do an extra lookup of the tablespace between fil_io() and the
completion of the operation, we must give fil_node_t::complete_io() a
chance to decrement the counter.
fil_close_tablespace(): Remove unused parameter trx, and document
that this is only invoked during the error handling of IMPORT TABLESPACE.
row_import_discard_changes(): Merged with the only caller,
row_import_cleanup(). Do not lock up the data dictionary while
invoking fil_close_tablespace().
logs_empty_and_mark_files_at_shutdown(): Do not invoke
fil_close_all_files(), to avoid a !needs_flush assertion failure
on fil_node_t::close().
innodb_shutdown(): Invoke os_aio_free() before fil_close_all_files().
fil_close_all_files(): Invoke fil_flush_file_spaces()
to ensure proper durability.
thread_pool::unbind(): Fix a crash that would occur on Windows
after srv_thread_pool->disable_aio() and os_file_close().
This fix was submitted by Vladislav Vaintroub.
Thanks to Matthias Leich and Axel Schwenke for extensive testing,
Vladislav Vaintroub for helpful comments, and Eugene Kosov for a review.
2020-06-05 12:35:46 +03:00
|
|
|
os_aio_free();
|
2020-10-26 16:04:12 +02:00
|
|
|
fil_space_t::close_all();
|
2017-06-29 23:10:46 +03:00
|
|
|
/* Exit any remaining threads. */
|
2020-10-26 15:04:24 +02:00
|
|
|
ut_ad(!buf_page_cleaner_is_active);
|
|
|
|
srv_shutdown_threads();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
|
|
|
if (srv_monitor_file) {
|
2019-05-23 12:55:03 +04:00
|
|
|
my_fclose(srv_monitor_file, MYF(MY_WME));
|
2014-02-26 19:11:54 +01:00
|
|
|
srv_monitor_file = 0;
|
|
|
|
if (srv_monitor_file_name) {
|
|
|
|
unlink(srv_monitor_file_name);
|
2016-08-12 11:17:45 +03:00
|
|
|
ut_free(srv_monitor_file_name);
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (srv_misc_tmpfile) {
|
2019-05-23 12:55:03 +04:00
|
|
|
my_fclose(srv_misc_tmpfile, MYF(MY_WME));
|
2014-02-26 19:11:54 +01:00
|
|
|
srv_misc_tmpfile = 0;
|
|
|
|
}
|
|
|
|
|
2019-05-17 14:32:53 +03:00
|
|
|
ut_ad(dict_sys.is_initialised() || !srv_was_started);
|
2018-01-17 19:43:08 +04:00
|
|
|
ut_ad(trx_sys.is_initialised() || !srv_was_started);
|
MDEV-26827 Make page flushing even faster
For more convenient monitoring of something that could greatly affect
the volume of page writes, we add the status variable
Innodb_buffer_pool_pages_split that was previously only available
via information_schema.innodb_metrics as "innodb_page_splits".
This was suggested by Axel Schwenke.
buf_flush_page_count: Replaced with buf_pool.stat.n_pages_written.
We protect buf_pool.stat (except n_page_gets) with buf_pool.mutex
and remove unnecessary export_vars indirection.
buf_pool.flush_list_bytes: Moved from buf_pool.stat.flush_list_bytes.
Protected by buf_pool.flush_list_mutex.
buf_pool_t::page_cleaner_status: Replaces buf_pool_t::n_flush_LRU_,
buf_pool_t::n_flush_list_, and buf_pool_t::page_cleaner_is_idle.
Protected by buf_pool.flush_list_mutex. We will exclusively broadcast
buf_pool.done_flush_list by the buf_flush_page_cleaner thread,
and only wait for it when communicating with buf_flush_page_cleaner.
There is no need to keep a count of pending writes by the
buf_pool.flush_list processing. A single flag suffices for that.
Waits for page write completion can be performed by
simply waiting on block->page.lock, or by invoking
buf_dblwr.wait_for_page_writes().
buf_LRU_block_free_non_file_page(): Broadcast buf_pool.done_free and
set buf_pool.try_LRU_scan when freeing a page. This would be
executed also as part of buf_page_write_complete().
buf_page_write_complete(): Do not broadcast buf_pool.done_flush_list,
and do not acquire buf_pool.mutex unless buf_pool.LRU eviction is needed.
Let buf_dblwr count all writes to persistent pages and broadcast a
condition variable when no outstanding writes remain.
buf_flush_page_cleaner(): Prioritize LRU flushing and eviction right after
"furious flushing" (lsn_limit). Simplify the conditions and reduce the
hold time of buf_pool.flush_list_mutex. Refuse to shut down
or sleep if buf_pool.ran_out(), that is, LRU eviction is needed.
buf_pool_t::page_cleaner_wakeup(): Add the optional parameter for_LRU.
buf_LRU_get_free_block(): Protect buf_lru_free_blocks_error_printed
with buf_pool.mutex. Invoke buf_pool.page_cleaner_wakeup(true) to
to ensure that buf_flush_page_cleaner() will process the LRU flush
request.
buf_do_LRU_batch(), buf_flush_list(), buf_flush_list_space():
Update buf_pool.stat.n_pages_written when submitting writes
(while holding buf_pool.mutex), not when completing them.
buf_page_t::flush(), buf_flush_discard_page(): Require that
the page U-latch be acquired upfront, and remove
buf_page_t::ready_for_flush().
buf_pool_t::delete_from_flush_list(): Remove the parameter "bool clear".
buf_flush_page(): Count pending page writes via buf_dblwr.
buf_flush_try_neighbors(): Take the block of page_id as a parameter.
If the tablespace is dropped before our page has been written out,
release the page U-latch.
buf_pool_invalidate(): Let the caller ensure that there are no
outstanding writes.
buf_flush_wait_batch_end(false),
buf_flush_wait_batch_end_acquiring_mutex(false):
Replaced with buf_dblwr.wait_for_page_writes().
buf_flush_wait_LRU_batch_end(): Replaces buf_flush_wait_batch_end(true).
buf_flush_list(): Remove some broadcast of buf_pool.done_flush_list.
buf_flush_buffer_pool(): Invoke also buf_dblwr.wait_for_page_writes().
buf_pool_t::io_pending(), buf_pool_t::n_flush_list(): Remove.
Outstanding writes are reflected by buf_dblwr.pending_writes().
buf_dblwr_t::init(): New function, to initialize the mutex and
the condition variables, but not the backing store.
buf_dblwr_t::is_created(): Replaces buf_dblwr_t::is_initialised().
buf_dblwr_t::pending_writes(), buf_dblwr_t::writes_pending:
Keeps track of writes of persistent data pages.
buf_flush_LRU(): Allow calls while LRU flushing may be in progress
in another thread.
Tested by Matthias Leich (correctness) and Axel Schwenke (performance)
2023-03-16 17:19:58 +02:00
|
|
|
ut_ad(buf_dblwr.is_created() || !srv_was_started
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
|| srv_read_only_mode
|
2017-02-01 15:47:33 +02:00
|
|
|
|| srv_force_recovery >= SRV_FORCE_NO_TRX_UNDO);
|
2018-02-22 20:46:42 +04:00
|
|
|
ut_ad(lock_sys.is_initialised() || !srv_was_started);
|
2018-04-27 10:06:14 +03:00
|
|
|
ut_ad(log_sys.is_initialised() || !srv_was_started);
|
2017-01-31 19:43:03 +02:00
|
|
|
|
2019-10-29 22:37:12 +01:00
|
|
|
dict_stats_deinit();
|
2014-12-22 16:53:17 +02:00
|
|
|
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
if (srv_started_redo) {
|
2017-01-31 19:43:03 +02:00
|
|
|
ut_ad(!srv_read_only_mode);
|
|
|
|
/* srv_shutdown_bg_undo_sources() already invoked
|
|
|
|
fts_optimize_shutdown(); dict_stats_shutdown(); */
|
|
|
|
|
|
|
|
fil_crypt_threads_cleanup();
|
2017-05-26 22:44:16 +03:00
|
|
|
btr_defragment_shutdown();
|
2017-01-31 19:43:03 +02:00
|
|
|
}
|
2015-12-20 12:33:58 +01:00
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
/* This must be disabled before closing the buffer pool
|
|
|
|
and closing the data dictionary. */
|
|
|
|
|
2017-02-23 23:05:12 +02:00
|
|
|
#ifdef BTR_CUR_HASH_ADAPT
|
2019-05-17 14:32:53 +03:00
|
|
|
if (dict_sys.is_initialised()) {
|
2020-05-27 13:03:06 +05:30
|
|
|
btr_search_disable();
|
2017-01-31 19:43:03 +02:00
|
|
|
}
|
2017-02-23 23:05:12 +02:00
|
|
|
#endif /* BTR_CUR_HASH_ADAPT */
|
2018-04-27 10:06:14 +03:00
|
|
|
log_sys.close();
|
2018-02-22 09:30:41 +02:00
|
|
|
purge_sys.close();
|
2018-03-30 00:33:58 +04:00
|
|
|
trx_sys.close();
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
|
|
|
buf_dblwr.close();
|
2018-02-22 20:46:42 +04:00
|
|
|
lock_sys.close();
|
2016-08-12 11:17:45 +03:00
|
|
|
trx_pool_close();
|
|
|
|
|
2014-02-26 19:11:54 +01:00
|
|
|
if (!srv_read_only_mode) {
|
2020-12-04 19:02:58 +02:00
|
|
|
mysql_mutex_destroy(&srv_monitor_file_mutex);
|
|
|
|
mysql_mutex_destroy(&srv_misc_tmpfile_mutex);
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
|
|
|
|
2019-05-17 14:32:53 +03:00
|
|
|
dict_sys.close();
|
2019-11-14 16:58:58 +02:00
|
|
|
btr_search_sys_free();
|
2014-02-26 19:11:54 +01:00
|
|
|
srv_free();
|
2018-03-28 09:00:06 +03:00
|
|
|
fil_system.close();
|
2014-02-26 19:11:54 +01:00
|
|
|
pars_lexer_close();
|
2019-05-24 16:19:38 +03:00
|
|
|
recv_sys.close();
|
2017-06-29 22:24:48 +03:00
|
|
|
|
2020-03-18 21:48:00 +02:00
|
|
|
ut_ad(buf_pool.is_initialised() || !srv_was_started);
|
|
|
|
buf_pool.close();
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2020-12-04 11:46:47 +02:00
|
|
|
srv_sys_space.shutdown();
|
|
|
|
if (srv_tmp_space.get_sanity_check_status()) {
|
2021-02-01 13:17:17 +02:00
|
|
|
if (fil_system.temp_space) {
|
|
|
|
fil_system.temp_space->close();
|
|
|
|
}
|
2020-12-04 11:46:47 +02:00
|
|
|
srv_tmp_space.delete_files();
|
|
|
|
}
|
|
|
|
srv_tmp_space.shutdown();
|
|
|
|
|
2021-08-31 14:09:47 +02:00
|
|
|
if (srv_stats.pages_page_compression_error)
|
|
|
|
ib::warn() << "Page compression errors: "
|
|
|
|
<< srv_stats.pages_page_compression_error;
|
|
|
|
|
2017-01-31 19:43:03 +02:00
|
|
|
if (srv_was_started && srv_print_verbose_log) {
|
2016-08-12 11:17:45 +03:00
|
|
|
ib::info() << "Shutdown completed; log sequence number "
|
MDEV-15132 Avoid accessing the TRX_SYS page
InnoDB maintains an internal persistent sequence of transaction
identifiers. This sequence is used for assigning both transaction
start identifiers (DB_TRX_ID=trx->id) and end identifiers (trx->no)
as well as end identifiers for the mysql.transaction_registry table
that was introduced in MDEV-12894.
TRX_SYS_TRX_ID_WRITE_MARGIN: Remove. After this many updates of
the sequence we used to update the TRX_SYS page. We can avoid accessing
the TRX_SYS page if we modify the InnoDB startup so that resurrecting
the sequence from other pages of the transaction system.
TRX_SYS_TRX_ID_STORE: Deprecate. The field only exists for the purpose
of upgrading from an earlier version of MySQL or MariaDB.
Starting with this fix, MariaDB will rely on the fields
TRX_UNDO_TRX_ID, TRX_UNDO_TRX_NO in the undo log header page of
each non-committed transaction, and on the new field
TRX_RSEG_MAX_TRX_ID in rollback segment header pages.
Because of this change, setting innodb_force_recovery=5 or 6 may cause
the system to recover with trx_sys.get_max_trx_id()==0. We must adjust
checks for invalid DB_TRX_ID and PAGE_MAX_TRX_ID accordingly.
We will change the startup and shutdown messages to display the
trx_sys.get_max_trx_id() in addition to the log sequence number.
trx_sys_t::flush_max_trx_id(): Remove.
trx_undo_mem_create_at_db_start(), trx_undo_lists_init():
Add an output parameter max_trx_id, to be updated from
TRX_UNDO_TRX_ID, TRX_UNDO_TRX_NO.
TRX_RSEG_MAX_TRX_ID: New field, for persisting
trx_sys.get_max_trx_id() at the time of the latest transaction commit.
Startup is not reading the undo log pages of committed transactions.
We want to avoid additional page accesses on startup, as well as
trouble when all undo logs have been emptied.
On startup, we will simply determine the maximum value from all pages
that are being read anyway.
TRX_RSEG_FORMAT: Redefined from TRX_RSEG_MAX_SIZE.
Old versions of InnoDB wrote uninitialized garbage to unused data fields.
Because of this, we cannot simply introduce a new field in the
rollback segment pages and expect it to be always zero, like it would
if the database was created by a recent enough InnoDB version.
Luckily, it looks like the field TRX_RSEG_MAX_SIZE was always written
as 0xfffffffe. We will indicate a new subformat of the page by writing
0 to this field. This has the nice side effect that after a downgrade
to older versions of InnoDB, transactions should fail to allocate any
undo log, that is, writes will be blocked. So, there is no problem of
getting corrupted transaction identifiers after downgrading.
trx_rseg_t::max_size: Remove.
trx_rseg_header_create(): Remove the parameter max_size=ULINT_MAX.
trx_purge_add_undo_to_history(): Update TRX_RSEG_MAX_SIZE
(and TRX_RSEG_FORMAT if needed). This is invoked on transaction commit.
trx_rseg_mem_restore(): If TRX_RSEG_FORMAT contains 0,
read TRX_RSEG_MAX_SIZE.
trx_rseg_array_init(): Invoke trx_sys.init_max_trx_id(max_trx_id + 1)
where max_trx_id was the maximum that was encountered in the rollback
segment pages and the undo log pages of recovered active, XA PREPARE,
or some committed transactions. (See trx_purge_add_undo_to_history()
which invokes trx_rsegf_set_nth_undo(..., FIL_NULL, ...);
not all committed transactions will be immediately detached from the
rollback segment header.)
2018-01-31 10:24:19 +02:00
|
|
|
<< srv_shutdown_lsn
|
|
|
|
<< "; transaction id " << trx_sys.get_max_trx_id();
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|
2019-11-14 16:58:58 +02:00
|
|
|
srv_thread_pool_end();
|
MDEV-23399: Performance regression with write workloads
The buffer pool refactoring in MDEV-15053 and MDEV-22871 shifted
the performance bottleneck to the page flushing.
The configuration parameters will be changed as follows:
innodb_lru_flush_size=32 (new: how many pages to flush on LRU eviction)
innodb_lru_scan_depth=1536 (old: 1024)
innodb_max_dirty_pages_pct=90 (old: 75)
innodb_max_dirty_pages_pct_lwm=75 (old: 0)
Note: The parameter innodb_lru_scan_depth will only affect LRU
eviction of buffer pool pages when a new page is being allocated. The
page cleaner thread will no longer evict any pages. It used to
guarantee that some pages will remain free in the buffer pool. Now, we
perform that eviction 'on demand' in buf_LRU_get_free_block().
The parameter innodb_lru_scan_depth(srv_LRU_scan_depth) is used as follows:
* When the buffer pool is being shrunk in buf_pool_t::withdraw_blocks()
* As a buf_pool.free limit in buf_LRU_list_batch() for terminating
the flushing that is initiated e.g., by buf_LRU_get_free_block()
The parameter also used to serve as an initial limit for unzip_LRU
eviction (evicting uncompressed page frames while retaining
ROW_FORMAT=COMPRESSED pages), but now we will use a hard-coded limit
of 100 or unlimited for invoking buf_LRU_scan_and_free_block().
The status variables will be changed as follows:
innodb_buffer_pool_pages_flushed: This includes also the count of
innodb_buffer_pool_pages_LRU_flushed and should work reliably,
updated one by one in buf_flush_page() to give more real-time
statistics. The function buf_flush_stats(), which we are removing,
was not called in every code path. For both counters, we will use
regular variables that are incremented in a critical section of
buf_pool.mutex. Note that show_innodb_vars() directly links to the
variables, and reads of the counters will *not* be protected by
buf_pool.mutex, so you cannot get a consistent snapshot of both variables.
The following INFORMATION_SCHEMA.INNODB_METRICS counters will be
removed, because the page cleaner no longer deals with writing or
evicting least recently used pages, and because the single-page writes
have been removed:
* buffer_LRU_batch_flush_avg_time_slot
* buffer_LRU_batch_flush_avg_time_thread
* buffer_LRU_batch_flush_avg_time_est
* buffer_LRU_batch_flush_avg_pass
* buffer_LRU_single_flush_scanned
* buffer_LRU_single_flush_num_scan
* buffer_LRU_single_flush_scanned_per_call
When moving to a single buffer pool instance in MDEV-15058, we missed
some opportunity to simplify the buf_flush_page_cleaner thread. It was
unnecessarily using a mutex and some complex data structures, even
though we always have a single page cleaner thread.
Furthermore, the buf_flush_page_cleaner thread had separate 'recovery'
and 'shutdown' modes where it was waiting to be triggered by some
other thread, adding unnecessary latency and potential for hangs in
relatively rarely executed startup or shutdown code.
The page cleaner was also running two kinds of batches in an
interleaved fashion: "LRU flush" (writing out some least recently used
pages and evicting them on write completion) and the normal batches
that aim to increase the MIN(oldest_modification) in the buffer pool,
to help the log checkpoint advance.
The buf_pool.flush_list flushing was being blocked by
buf_block_t::lock for no good reason. Furthermore, if the FIL_PAGE_LSN
of a page is ahead of log_sys.get_flushed_lsn(), that is, what has
been persistently written to the redo log, we would trigger a log
flush and then resume the page flushing. This would unnecessarily
limit the performance of the page cleaner thread and trigger the
infamous messages "InnoDB: page_cleaner: 1000ms intended loop took 4450ms.
The settings might not be optimal" that were suppressed in
commit d1ab89037a518fcffbc50c24e4bd94e4ec33aed0 unless log_warnings>2.
Our revised algorithm will make log_sys.get_flushed_lsn() advance at
the start of buf_flush_lists(), and then execute a 'best effort' to
write out all pages. The flush batches will skip pages that were modified
since the log was written, or are are currently exclusively locked.
The MDEV-13670 message "page_cleaner: 1000ms intended loop took" message
will be removed, because by design, the buf_flush_page_cleaner() should
not be blocked during a batch for extended periods of time.
We will remove the single-page flushing altogether. Related to this,
the debug parameter innodb_doublewrite_batch_size will be removed,
because all of the doublewrite buffer will be used for flushing
batches. If a page needs to be evicted from the buffer pool and all
100 least recently used pages in the buffer pool have unflushed
changes, buf_LRU_get_free_block() will execute buf_flush_lists() to
write out and evict innodb_lru_flush_size pages. At most one thread
will execute buf_flush_lists() in buf_LRU_get_free_block(); other
threads will wait for that LRU flushing batch to finish.
To improve concurrency, we will replace the InnoDB ib_mutex_t and
os_event_t native mutexes and condition variables in this area of code.
Most notably, this means that the buffer pool mutex (buf_pool.mutex)
is no longer instrumented via any InnoDB interfaces. It will continue
to be instrumented via PERFORMANCE_SCHEMA.
For now, both buf_pool.flush_list_mutex and buf_pool.mutex will be
declared with MY_MUTEX_INIT_FAST (PTHREAD_MUTEX_ADAPTIVE_NP). The critical
sections of buf_pool.flush_list_mutex should be shorter than those for
buf_pool.mutex, because in the worst case, they cover a linear scan of
buf_pool.flush_list, while the worst case of a critical section of
buf_pool.mutex covers a linear scan of the potentially much longer
buf_pool.LRU list.
mysql_mutex_is_owner(), safe_mutex_is_owner(): New predicate, usable
with SAFE_MUTEX. Some InnoDB debug assertions need this predicate
instead of mysql_mutex_assert_owner() or mysql_mutex_assert_not_owner().
buf_pool_t::n_flush_LRU, buf_pool_t::n_flush_list:
Replaces buf_pool_t::init_flush[] and buf_pool_t::n_flush[].
The number of active flush operations.
buf_pool_t::mutex, buf_pool_t::flush_list_mutex: Use mysql_mutex_t
instead of ib_mutex_t, to have native mutexes with PERFORMANCE_SCHEMA
and SAFE_MUTEX instrumentation.
buf_pool_t::done_flush_LRU: Condition variable for !n_flush_LRU.
buf_pool_t::done_flush_list: Condition variable for !n_flush_list.
buf_pool_t::do_flush_list: Condition variable to wake up the
buf_flush_page_cleaner when a log checkpoint needs to be written
or the server is being shut down. Replaces buf_flush_event.
We will keep using timed waits (the page cleaner thread will wake
_at least_ once per second), because the calculations for
innodb_adaptive_flushing depend on fixed time intervals.
buf_dblwr: Allocate statically, and move all code to member functions.
Use a native mutex and condition variable. Remove code to deal with
single-page flushing.
buf_dblwr_check_block(): Make the check debug-only. We were spending
a significant amount of execution time in page_simple_validate_new().
flush_counters_t::unzip_LRU_evicted: Remove.
IORequest: Make more members const. FIXME: m_fil_node should be removed.
buf_flush_sync_lsn: Protect by std::atomic, not page_cleaner.mutex
(which we are removing).
page_cleaner_slot_t, page_cleaner_t: Remove many redundant members.
pc_request_flush_slot(): Replaces pc_request() and pc_flush_slot().
recv_writer_thread: Remove. Recovery works just fine without it, if we
simply invoke buf_flush_sync() at the end of each batch in
recv_sys_t::apply().
recv_recovery_from_checkpoint_finish(): Remove. We can simply call
recv_sys.debug_free() directly.
srv_started_redo: Replaces srv_start_state.
SRV_SHUTDOWN_FLUSH_PHASE: Remove. logs_empty_and_mark_files_at_shutdown()
can communicate with the normal page cleaner loop via the new function
flush_buffer_pool().
buf_flush_remove(): Assert that the calling thread is holding
buf_pool.flush_list_mutex. This removes unnecessary mutex operations
from buf_flush_remove_pages() and buf_flush_dirty_pages(),
which replace buf_LRU_flush_or_remove_pages().
buf_flush_lists(): Renamed from buf_flush_batch(), with simplified
interface. Return the number of flushed pages. Clarified comments and
renamed min_n to max_n. Identify LRU batch by lsn=0. Merge all the functions
buf_flush_start(), buf_flush_batch(), buf_flush_end() directly to this
function, which was their only caller, and remove 2 unnecessary
buf_pool.mutex release/re-acquisition that we used to perform around
the buf_flush_batch() call. At the start, if not all log has been
durably written, wait for a background task to do it, or start a new
task to do it. This allows the log write to run concurrently with our
page flushing batch. Any pages that were skipped due to too recent
FIL_PAGE_LSN or due to them being latched by a writer should be flushed
during the next batch, unless there are further modifications to those
pages. It is possible that a page that we must flush due to small
oldest_modification also carries a recent FIL_PAGE_LSN or is being
constantly modified. In the worst case, all writers would then end up
waiting in log_free_check() to allow the flushing and the checkpoint
to complete.
buf_do_flush_list_batch(): Clarify comments, and rename min_n to max_n.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_flush_space(): Auxiliary function to look up a tablespace for
page flushing.
buf_flush_page(): Defer the computation of space->full_crc32(). Never
call log_write_up_to(), but instead skip persistent pages whose latest
modification (FIL_PAGE_LSN) is newer than the redo log. Also skip
pages on which we cannot acquire a shared latch without waiting.
buf_flush_try_neighbors(): Do not bother checking buf_fix_count
because buf_flush_page() will no longer wait for the page latch.
Take the tablespace as a parameter, and only execute this function
when innodb_flush_neighbors>0. Avoid repeated calls of page_id_t::fold().
buf_flush_relocate_on_flush_list(): Declare as cold, and push down
a condition from the callers.
buf_flush_check_neighbor(): Take id.fold() as a parameter.
buf_flush_sync(): Ensure that the buf_pool.flush_list is empty,
because the flushing batch will skip pages whose modifications have
not yet been written to the log or were latched for modification.
buf_free_from_unzip_LRU_list_batch(): Remove redundant local variables.
buf_flush_LRU_list_batch(): Let the caller buf_do_LRU_batch() initialize
the counters, and report n->evicted.
Cache the last looked up tablespace. If neighbor flushing is not applicable,
invoke buf_flush_page() directly, avoiding a page lookup in between.
buf_do_LRU_batch(): Return the number of pages flushed.
buf_LRU_free_page(): Only release and re-acquire buf_pool.mutex if
adaptive hash index entries are pointing to the block.
buf_LRU_get_free_block(): Do not wake up the page cleaner, because it
will no longer perform any useful work for us, and we do not want it
to compete for I/O while buf_flush_lists(innodb_lru_flush_size, 0)
writes out and evicts at most innodb_lru_flush_size pages. (The
function buf_do_LRU_batch() may complete after writing fewer pages if
more than innodb_lru_scan_depth pages end up in buf_pool.free list.)
Eliminate some mutex release-acquire cycles, and wait for the LRU
flush batch to complete before rescanning.
buf_LRU_check_size_of_non_data_objects(): Simplify the code.
buf_page_write_complete(): Remove the parameter evict, and always
evict pages that were part of an LRU flush.
buf_page_create(): Take a pre-allocated page as a parameter.
buf_pool_t::free_block(): Free a pre-allocated block.
recv_sys_t::recover_low(), recv_sys_t::apply(): Preallocate the block
while not holding recv_sys.mutex. During page allocation, we may
initiate a page flush, which in turn may initiate a log flush, which
would require acquiring log_sys.mutex, which should always be acquired
before recv_sys.mutex in order to avoid deadlocks. Therefore, we must
not be holding recv_sys.mutex while allocating a buffer pool block.
BtrBulk::logFreeCheck(): Skip a redundant condition.
row_undo_step(): Do not invoke srv_inc_activity_count() for every row
that is being rolled back. It should suffice to invoke the function in
trx_flush_log_if_needed() during trx_t::commit_in_memory() when the
rollback completes.
sync_check_enable(): Remove. We will enable innodb_sync_debug from the
very beginning.
Reviewed by: Vladislav Vaintroub
2020-10-15 12:10:42 +03:00
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srv_started_redo = false;
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2017-04-25 09:26:01 +03:00
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srv_was_started = false;
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srv_start_has_been_called = false;
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2014-02-26 19:11:54 +01:00
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}
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2016-08-12 11:17:45 +03:00
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/** Get the meta-data filename from the table name for a
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single-table tablespace.
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@param[in] table table object
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@param[out] filename filename
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@param[in] max_len filename max length */
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2014-02-26 19:11:54 +01:00
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void
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srv_get_meta_data_filename(
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2016-09-06 09:43:16 +03:00
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dict_table_t* table,
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char* filename,
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ulint max_len)
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2014-02-26 19:11:54 +01:00
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{
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2016-08-12 11:17:45 +03:00
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ulint len;
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char* path;
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/* Make sure the data_dir_path is set. */
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2022-03-16 17:19:13 +02:00
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dict_get_and_save_data_dir_path(table);
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2014-02-26 19:11:54 +01:00
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MDEV-25312 Replace fil_space_t::name with fil_space_t::name()
A consistency check for fil_space_t::name is causing recovery failures
in MDEV-25180 (Atomic ALTER TABLE). So, we'd better remove that field
altogether.
fil_space_t::name was more or less a copy of dict_table_t::name
(except for some special cases), and it was not being used for
anything useful.
There used to be a name_hash, but it had been removed already in
commit a75dbfd7183cc96680f3e3e684fd36500dac8158 (MDEV-12266).
We will also remove os_normalize_path(), OS_PATH_SEPARATOR,
OS_PATH_SEPATOR_ALT. On Microsoft Windows, we will treat \ and /
roughly in the same way. The intention is that for per-table
tablespaces, the filenames will always follow the pattern
prefix/databasename/tablename.ibd. (Any \ in the prefix must not
be converted.)
ut_basename_noext(): Remove (unused function).
read_link_file(): Replaces RemoteDatafile::read_link_file().
We will ensure that the last two path component separators are
forward slashes (converting up to 2 trailing backslashes on
Microsoft Windows), so that everywhere else we can
assume that data file names end in "/databasename/tablename.ibd".
Note: On Microsoft Windows, path names that start with \\?\ must
not contain / as path component separators. Previously, such paths
did work in the DATA DIRECTORY argument of InnoDB tables.
Reviewed by: Vladislav Vaintroub
2021-04-07 18:01:13 +03:00
|
|
|
const char* data_dir_path = DICT_TF_HAS_DATA_DIR(table->flags)
|
|
|
|
? table->data_dir_path : nullptr;
|
|
|
|
ut_ad(!DICT_TF_HAS_DATA_DIR(table->flags) || data_dir_path);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
MDEV-25312 Replace fil_space_t::name with fil_space_t::name()
A consistency check for fil_space_t::name is causing recovery failures
in MDEV-25180 (Atomic ALTER TABLE). So, we'd better remove that field
altogether.
fil_space_t::name was more or less a copy of dict_table_t::name
(except for some special cases), and it was not being used for
anything useful.
There used to be a name_hash, but it had been removed already in
commit a75dbfd7183cc96680f3e3e684fd36500dac8158 (MDEV-12266).
We will also remove os_normalize_path(), OS_PATH_SEPARATOR,
OS_PATH_SEPATOR_ALT. On Microsoft Windows, we will treat \ and /
roughly in the same way. The intention is that for per-table
tablespaces, the filenames will always follow the pattern
prefix/databasename/tablename.ibd. (Any \ in the prefix must not
be converted.)
ut_basename_noext(): Remove (unused function).
read_link_file(): Replaces RemoteDatafile::read_link_file().
We will ensure that the last two path component separators are
forward slashes (converting up to 2 trailing backslashes on
Microsoft Windows), so that everywhere else we can
assume that data file names end in "/databasename/tablename.ibd".
Note: On Microsoft Windows, path names that start with \\?\ must
not contain / as path component separators. Previously, such paths
did work in the DATA DIRECTORY argument of InnoDB tables.
Reviewed by: Vladislav Vaintroub
2021-04-07 18:01:13 +03:00
|
|
|
path = fil_make_filepath(data_dir_path, table->name, CFG,
|
|
|
|
data_dir_path != nullptr);
|
2014-02-26 19:11:54 +01:00
|
|
|
ut_a(path);
|
2019-10-30 07:31:39 +02:00
|
|
|
len = strlen(path);
|
2014-02-26 19:11:54 +01:00
|
|
|
ut_a(max_len >= len);
|
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
strcpy(filename, path);
|
2014-02-26 19:11:54 +01:00
|
|
|
|
2016-08-12 11:17:45 +03:00
|
|
|
ut_free(path);
|
2014-02-26 19:11:54 +01:00
|
|
|
}
|