MariaDB 10.0/MySQL 5.6 using innodb-page-size!=16K
The storage format of FSP_SPACE_FLAGS was accidentally broken
already in MariaDB 10.1.0. This fix is bringing the format in
line with other MySQL and MariaDB release series.
Please refer to the comments that were added to fsp0fsp.h
for details.
This is an INCOMPATIBLE CHANGE that affects users of
page_compression and non-default innodb_page_size. Upgrading
to this release will correct the flags in the data files.
If you want to downgrade to earlier MariaDB 10.1.x, please refer
to the test innodb.101_compatibility how to reset the
FSP_SPACE_FLAGS in the files.
NOTE: MariaDB 10.1.0 to 10.1.20 can misinterpret
uncompressed data files with innodb_page_size=4k or 64k as
compressed innodb_page_size=16k files, and then probably fail
when trying to access the pages. See the comments in the
function fsp_flags_convert_from_101() for detailed analysis.
Move PAGE_COMPRESSION to FSP_SPACE_FLAGS bit position 16.
In this way, compressed innodb_page_size=16k tablespaces will not
be mistaken for uncompressed ones by MariaDB 10.1.0 to 10.1.20.
Derive PAGE_COMPRESSION_LEVEL, ATOMIC_WRITES and DATA_DIR from the
dict_table_t::flags when the table is available, in
fil_space_for_table_exists_in_mem() or fil_open_single_table_tablespace().
During crash recovery, fil_load_single_table_tablespace() will use
innodb_compression_level for the PAGE_COMPRESSION_LEVEL.
FSP_FLAGS_MEM_MASK: A bitmap of the memory-only fil_space_t::flags
that are not to be written to FSP_SPACE_FLAGS. Currently, these will
include PAGE_COMPRESSION_LEVEL, ATOMIC_WRITES and DATA_DIR.
Introduce the macro FSP_FLAGS_PAGE_SSIZE(). We only support
one innodb_page_size for the whole instance.
When creating a dummy tablespace for the redo log, use
fil_space_t::flags=0. The flags are never written to the redo log files.
Remove many FSP_FLAGS_SET_ macros.
dict_tf_verify_flags(): Remove. This is basically only duplicating
the logic of dict_tf_to_fsp_flags(), used in a debug assertion.
fil_space_t::mark: Remove. This flag was not used for anything.
fil_space_for_table_exists_in_mem(): Remove the unnecessary parameter
mark_space, and add a parameter for table flags. Check that
fil_space_t::flags match the table flags, and adjust the (memory-only)
flags based on the table flags.
fil_node_open_file(): Remove some redundant or unreachable conditions,
do not use stderr for output, and avoid unnecessary server aborts.
fil_user_tablespace_restore_page(): Convert the flags, so that the
correct page_size will be used when restoring a page from the
doublewrite buffer.
fil_space_get_page_compressed(), fsp_flags_is_page_compressed(): Remove.
It suffices to have fil_space_is_page_compressed().
FSP_FLAGS_WIDTH_DATA_DIR, FSP_FLAGS_WIDTH_PAGE_COMPRESSION_LEVEL,
FSP_FLAGS_WIDTH_ATOMIC_WRITES: Remove, because these flags do not
exist in the FSP_SPACE_FLAGS but only in memory.
fsp_flags_try_adjust(): New function, to adjust the FSP_SPACE_FLAGS
in page 0. Called by fil_open_single_table_tablespace(),
fil_space_for_table_exists_in_mem(), innobase_start_or_create_for_mysql()
except if --innodb-read-only is active.
fsp_flags_is_valid(ulint): Reimplement from the scratch, with
accurate comments. Do not display any details of detected
inconsistencies, because the output could be confusing when
dealing with MariaDB 10.1.x data files.
fsp_flags_convert_from_101(ulint): Convert flags from buggy
MariaDB 10.1.x format, or return ULINT_UNDEFINED if the flags
cannot be in MariaDB 10.1.x format.
fsp_flags_match(): Check the flags when probing files.
Implemented based on fsp_flags_is_valid()
and fsp_flags_convert_from_101().
dict_check_tablespaces_and_store_max_id(): Do not access the
page after committing the mini-transaction.
IMPORT TABLESPACE fixes:
AbstractCallback::init(): Convert the flags.
FetchIndexRootPages::operator(): Check that the tablespace flags match the
table flags. Do not attempt to convert tablespace flags to table flags,
because the conversion would necessarily be lossy.
PageConverter::update_header(): Write back the correct flags.
This takes care of the flags in IMPORT TABLESPACE.
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.
after aborted InnoDB startup
This bug was repeatable by starting MariaDB 10.2 with an
invalid option, such as --innodb-flush-method=foo.
It is not repeatable in MariaDB 10.1 in the same way, but the
problem exists already there.
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.
Problem was that for encryption we use temporary scratch area for
reading and writing tablespace pages. But if page was not really
decrypted the correct updated page was not moved to scratch area
that was then written. This can happen e.g. for page 0 as it is
newer encrypted even if encryption is enabled and as we write
the contents of old page 0 to tablespace it contained naturally
incorrect space_id that is then later noted and error message
was written. Updated page with correct space_id was lost.
If tablespace is encrypted we use additional
temporary scratch area where pages are read
for decrypting readptr == crypt_io_buffer != io_buffer.
Destination for decryption is a buffer pool block
block->frame == dst == io_buffer that is updated.
Pages that did not require decryption even when
tablespace is marked as encrypted are not copied
instead block->frame is set to src == readptr.
If tablespace was encrypted we copy updated page to
writeptr != io_buffer. This fixes above bug.
For encryption we again use temporary scratch area
writeptr != io_buffer == dst
that is then written to the tablespace
(1) For normal tables src == dst == writeptr
ut_ad(!encrypted && !page_compressed ?
src == dst && dst == writeptr + (i * size):1);
(2) For page compressed tables src == dst == writeptr
ut_ad(page_compressed && !encrypted ?
src == dst && dst == writeptr + (i * size):1);
(3) For encrypted tables src != dst != writeptr
ut_ad(encrypted ?
src != dst && dst != writeptr + (i * size):1);
Replace all exit() calls in InnoDB with abort() [possibly via ut_a()].
Calling exit() in a multi-threaded program is problematic also for
the reason that other threads could see corrupted data structures
while some data structures are being cleaned up by atexit() handlers
or similar.
In the long term, all these calls should be replaced with something
that returns an error all the way up the call stack.
Make some global fil_crypt_ variables static.
fil_close(): Call mutex_free(&fil_system->mutex) also in InnoDB, not
only in XtraDB. In InnoDB, sync_close() was called before fil_close().
innobase_shutdown_for_mysql(): Call fil_close() before sync_close(),
similar to XtraDB shutdown.
fil_space_crypt_cleanup(): Call mutex_free() to pair with
fil_space_crypt_init().
fil_crypt_threads_cleanup(): Call mutex_free() to pair with
fil_crypt_threads_init().
Reduce the number of calls to encryption_get_key_get_latest_version
when doing key rotation with two different methods:
(1) We need to fetch key information when tablespace not yet
have a encryption information, invalid keys are handled now
differently (see below). There was extra call to detect
if key_id is not found on key rotation.
(2) If key_id is not found from encryption plugin, do not
try fetching new key_version for it as it will fail anyway.
We store return value from encryption_get_key_get_latest_version
call and if it returns ENCRYPTION_KEY_VERSION_INVALID there
is no need to call it again.
Two problems:
(1) When pushing warning to sql-layer we need to check that thd != NULL
to avoid NULL-pointer reference.
(2) At tablespace key rotation if used key_id is not found from
encryption plugin tablespace should not be rotated.
Analysis: By design InnoDB was reading first page of every .ibd file
at startup to find out is tablespace encrypted or not. This is
because tablespace could have been encrypted always, not
encrypted newer or encrypted based on configuration and this
information can be find realible only from first page of .ibd file.
Fix: Do not read first page of every .ibd file at startup. Instead
whenever tablespace is first time accedded we will read the first
page to find necessary information about tablespace encryption
status.
TODO: Add support for SYS_TABLEOPTIONS where all table options
encryption information included will be stored.
MySQL 5.6 do not work with MariaDB 10.1
Analysis: Problem is that tablespace flags bit DATA_DIR
is on different position on MySQL 5.6 compared to
MariaDB 10.1.
Fix: If we detect that there is difference between dictionary
flags and tablespace flags we remove DATA_DIR flag and compare
again. Remote tablespace is tried to locate even in case
when DATA_DIR flag is not set.
Analysis: When pages in doublewrite buffer are analyzed compressed
pages do not have correct checksum.
Fix: Decompress page before checksum is compared. If decompression
fails we still check checksum and corrupted pages are found.
If decompression succeeds, page now contains the original
checksum.
Problem was that link file (.isl) is also opened using O_DIRECT
mode and if this fails the whole create table fails on internal
error.
Fixed by not using O_DIRECT on link files as they are used only
on create table and startup and do not contain real data.
O_DIRECT failures are successfully ignored for data files
if O_DIRECT is not supported by file system on used
data directory.
Make sure that on decrypt we do not try to reference
NULL pointer and if page contains undefined
FIL_PAGE_FILE_FLUSH_LSN field on when page is not
the first page or page is not in system tablespace,
clear it.
There was two problems. Firstly, if page in ibuf is encrypted but
decrypt failed we should not allow InnoDB to start because
this means that system tablespace is encrypted and not usable.
Secondly, if page decrypt is detected we should return false
from buf_page_decrypt_after_read.
Analysis: Lengths which are not UNIV_SQL_NULL, but bigger than the following
number indicate that a field contains a reference to an externally
stored part of the field in the tablespace. The length field then
contains the sum of the following flag and the locally stored len.
This was incorrectly set to
define UNIV_EXTERN_STORAGE_FIELD (UNIV_SQL_NULL - UNIV_PAGE_SIZE_MAX)
When it should be
define UNIV_EXTERN_STORAGE_FIELD (UNIV_SQL_NULL - UNIV_PAGE_SIZE_DEF)
Additionally, we need to disable support for > 16K page size for
row compressed tables because a compressed page directory entry
reserves 14 bits for the start offset and 2 bits for flags.
This limits the uncompressed page size to 16k. To support
larger pages page directory entry needs to be larger.
Analysis: Problem is that punch hole does not know the actual page size
of the page and does the page belong to an data file or to a log file.
Fix: Pass down the file type and page size to os layer to be used
when trim is called. Also fix unsafe null pointer access to
actual write_size.
Analysis: Problem sees to be the fact that we allow creating or altering
table to use encryption_key_id that does not exists in case where
original table is not encrypted currently. Secondly we should not
do key rotation to tables that are not encrypted or tablespaces
that can't be found from tablespace cache.
Fix: Do not allow creating unencrypted table with nondefault encryption key
and do not rotate tablespaces that are not encrypted (FIL_SPACE_ENCRYPTION_OFF)
or can't be found from tablespace cache.
Added encryption support for online alter table where InnoDB temporary
files are used. Added similar support also for tables containing
full text-indexes.
Made sure that table remains encrypted during discard and import
tablespace.
Analysis: Problem was that in fil_read_first_page we do find that
table has encryption information and that encryption service
or used key_id is not available. But, then we just printed
fatal error message that causes above assertion.
Fix: When we open single table tablespace if it has encryption
information (crypt_data) store this crypt data to the table
structure. When we open a table and we find out that tablespace
is not available, check has table a encryption information
and from there is encryption service or used key_id is not available.
If it is, add additional warning for SQL-layer.
Analysis: Problem was that in fil_read_first_page we do find that
table has encryption information and that encryption service
or used key_id is not available. But, then we just printed
fatal error message that causes above assertion.
Fix: When we open single table tablespace if it has encryption
information (crypt_data) store this crypt data to the table
structure. When we open a table and we find out that tablespace
is not available, check has table a encryption information
and from there is encryption service or used key_id is not available.
If it is, add additional warning for SQL-layer.