Problem:
=======
InnoDB cleans all temporary undo logs during commit. During rollback
of secondary index entry, InnoDB tries to build the previous version
of clustered index. It leads to access of freed undo page during
previous transaction commit and it leads to undo log corruption.
Solution:
=========
During rollback, temporary undo logs should not try to build
the previous version of the record.
Rollback attempted to dereference DB_ROLL_PTR=0, which cannot possibly
be a valid undo log pointer. A safe canonical value would be
roll_ptr_t(1) << ROLL_PTR_INSERT_FLAG_POS
which is what was chosen in MDEV-12288.
This bug was reproduced in 10.3 only. Potentially, the problem could
have been introduced by MDEV-11415, which suppresses undo logging for
ALGORITHM=COPY operations. In those operations, we should actually
have written the safe value of DB_ROLL_PTR instead of writing 0.
However, the test in commit 5421e3aee7
demonstrates that access to the rebuilt table by earlier-started
transactions should actually have been refused with ER_TABLE_DEF_CHANGED.
btr_cur_ins_lock_and_undo(): When undo logging is disabled, use the
safe value of DB_ROLL_PTR.
btr_cur_optimistic_insert(): Validate the DB_TRX_ID,DB_ROLL_PTR before
inserting into a clustered index leaf page.
ins_node_t::sys_buf[]: Replaces row_id_buf and trx_id_buf and some
heap usage.
row_ins_alloc_sys_fields(): Initialize ins_node_t::sys_buf[].
trx_undo_page_report_modify(): Assert that the DB_ROLL_PTR is not 0.
trx_undo_get_undo_rec_low(): Assert that the roll_ptr is valid before
trying to dereference it.
dict_index_t::is_primary(): Check if the index is the primary key.
If a crash occurs during ALTER TABLE…ALGORITHM=COPY, InnoDB would spend
a lot of time rolling back writes to the intermediate copy of the table.
To reduce the amount of busy work done, a work-around was introduced in
commit fd069e2bb3 in MySQL 4.1.8 and 5.0.2,
to commit the transaction after every 10,000 inserted rows.
A proper fix would have been to disable the undo logging altogether and
to simply drop the intermediate copy of the table on subsequent server
startup. This is what happens in MariaDB 10.3 with MDEV-14717,MDEV-14585.
In MariaDB 10.2, the intermediate copy of the table would be left behind
with a name starting with the string #sql.
This is a backport of a bug fix from MySQL 8.0.0 to MariaDB,
contributed by jixianliang <271365745@qq.com>.
Unlike recent MySQL, MariaDB supports ALTER IGNORE. For that operation
InnoDB must for now keep the undo logging enabled, so that the latest
row can be rolled back in case of an error.
In Galera cluster, the LOAD DATA statement will retain the existing
behaviour and commit the transaction after every 10,000 rows if
the parameter wsrep_load_data_splitting=ON is set. The logic to do
so (the wsrep_load_data_split() function and the call
handler::extra(HA_EXTRA_FAKE_START_STMT)) are joint work
by Ji Xianliang and Marko Mäkelä.
The original fix:
Author: Thirunarayanan Balathandayuthapani <thirunarayanan.balathandayuth@oracle.com>
Date: Wed Dec 2 16:09:15 2015 +0530
Bug#17479594 AVOID INTERMEDIATE COMMIT WHILE DOING ALTER TABLE ALGORITHM=COPY
Problem:
During ALTER TABLE, we commit and restart the transaction for every
10,000 rows, so that the rollback after recovery would not take so long.
Fix:
Suppress the undo logging during copy alter operation. If fts_index is
present then insert directly into fts auxiliary table rather
than doing at commit time.
ha_innobase::num_write_row: Remove the variable.
ha_innobase::write_row(): Remove the hack for committing every 10000 rows.
row_lock_table_for_mysql(): Remove the extra 2 parameters.
lock_get_src_table(), lock_is_table_exclusive(): Remove.
Reviewed-by: Marko Mäkelä <marko.makela@oracle.com>
Reviewed-by: Shaohua Wang <shaohua.wang@oracle.com>
Reviewed-by: Jon Olav Hauglid <jon.hauglid@oracle.com>
trx_undo_page_report_modify(): For SPATIAL INDEX, keep logging
updated off-page columns twice, so that
the minimum bounding rectangle (MBR) will be logged.
Avoiding the redundant logging would require larger changes
to the undo log format.
row_build_index_entry_low(): Handle SPATIAL_UNKNOWN more robustly,
by refusing to purge the record from the spatial index.
We can get this code when processing old undo log from 10.2.10 or
10.2.11 (the releases affected by MDEV-14799, which was a regression
from MDEV-14051).
When MySQL 5.7 introduced indexed virtual columns, it introduced
several bugs into the online table-rebuilding ALTER, that is,
the row_log_table_apply() family of functions.
The online_log format that was introduced for online table-rebuilding
ALTER in MySQL 5.6 should be sufficient. Ideally, any indexed virtual
column values would be evaluated based on the log records in the temporary
file. There is no need to log virtual column values.
(For ADD INDEX, that is row_log_apply(), we always must log the values of
the keys, no matter if the columns are virtual.)
Because omitting the virtual column values removes any chance of
row_log_table_apply() working with indexed virtual columns, we
will for now refuse LOCK=NONE in table-rebuilding ALTER operations
when indexes on virtual columns exist. This restriction would be
lifted in MDEV-14341.
innobase_indexed_virtual_exist(): New predicate, to determine if
indexed virtual columns exist in a table definition.
ha_innobase::check_if_supported_inplace_alter(): Refuse online rebuild
if indexed virtual columns exist.
rec_get_converted_size_temp_v(), rec_convert_dtuple_to_temp_v(): Remove.
row_log_table_delete(), row_log_table_update(, row_log_table_insert():
Remove parameters for virtual columns.
trx_undo_read_v_rows(): Remove the col_map parameter.
row_log_table_apply(): Do not deal with virtual columns.
Replace all references in InnoDB and XtraDB error log messages
to bugs.mysql.com with references to https://jira.mariadb.org/.
The original merge
commit 4274d0bf57
was accidentally reverted by the subsequent merge
commit 3b35d745c3
upd_field_set_field_no(): Remove the unused parameter trx, and
remove a debug message. In debug builds, the out-of-bounds access
would still be caught by dict_index_get_nth_col().
trx_undo_update_rec_get_update(): Remove the unnecessary parameter trx.
This should affect debug builds only. Debug builds will check that
the status bits of ROW_FORMAT!=REDUNDANT records match the is_leaf
parameter.
The only observable change to non-debug should be the addition of
the is_leaf parameter to the function rec_copy_prefix_to_dtuple(),
and the removal of some calls to update the adaptive hash index
(it is only built for the leaf pages).
This change should have been made in MySQL 5.0.3, instead of
introducing the status flags in the ROW_FORMAT=COMPACT record header.
This is preparation for MDEV-12288, which would set DB_TRX_ID=0
when purging history. Also with that change in place, delete-marked
records must always refer to an undo log record via a nonzero
DB_TRX_ID column. (The DB_TRX_ID is only present in clustered index
leaf page records.)
btr_cur_parse_del_mark_set_clust_rec(), rec_get_trx_id():
Statically allocate the offsets
(should never use the heap). Add some debug assertions.
Replace some use of rec_get_trx_id() with row_get_rec_trx_id().
trx_undo_report_row_operation(): Add some sanity checks that are
common for all operations that produce undo log.
Fix a -fsanitizer=undefined warning that trx_undo_report_row_operation()
was being passed thr=NULL when the BTR_NO_UNDO_LOG_FLAG flag was set.
trx_undo_report_row_operation(): Remove the first two parameters.
The parameter clust_entry!=NULL distinguishes inserts from updates.
This should be a non-functional change (no observable change in
behaviour; slightly smaller code).
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.
InnoDB defines some functions that are not called at all.
Other functions are called, but only from the same compilation unit.
Remove some function declarations and definitions, and add 'static'
keywords. Some symbols must be kept for separately compiled tools,
such as innochecksum.
Also, remove empty .ic files that were not removed by my MySQL commit.
Problem:
InnoDB used to support a compilation mode that allowed to choose
whether the function definitions in .ic files are to be inlined or not.
This stopped making sense when InnoDB moved to C++ in MySQL 5.6
(and ha_innodb.cc started to #include .ic files), and more so in
MySQL 5.7 when inline methods and functions were introduced
in .h files.
Solution:
Remove all references to UNIV_NONINL and UNIV_MUST_NOT_INLINE from
all files, assuming that the symbols are never defined.
Remove the files fut0fut.cc and ut0byte.cc which only mattered when
UNIV_NONINL was defined.
Starting with MySQL 5.7, temporary tables in InnoDB are handled
differently from persistent tables. Because temporary tables are
private to a connection, concurrency control and multi-versioning
(MVCC) are not applicable. For performance reasons, purge is
disabled as well. Rollback is supported for temporary tables;
that is why we have the temporary undo logs in the first place.
Because MVCC and purge are disabled for temporary tables, we should
discard all temporary undo logs already at transaction commit,
just like we discard the persistent insert_undo logs. Before this
change, update_undo logs were being preserved.
trx_temp_undo_t: A wrapper for temporary undo logs, comprising
a rollback segment and a single temporary undo log.
trx_rsegs_t::m_noredo: Use trx_temp_undo_t.
(Instead of insert_undo, update_undo, there will be a single undo.)
trx_is_noredo_rseg_updated(), trx_is_rseg_assigned(): Remove.
trx_undo_add_page(): Remove the parameter undo_ptr.
Acquire and release the rollback segment mutex inside the function.
trx_undo_free_last_page(): Remove the parameter trx.
trx_undo_truncate_end(): Remove the parameter trx, and add the
parameter is_temp. Clean up the code a bit.
trx_undo_assign_undo(): Split the parameter undo_ptr into rseg, undo.
trx_undo_commit_cleanup(): Renamed from trx_undo_insert_cleanup().
Replace the parameter undo_ptr with undo.
This will discard the temporary undo or insert_undo log at
commit/rollback.
trx_purge_add_update_undo_to_history(), trx_undo_update_cleanup():
Remove 3 parameters. Always operate on the persistent update_undo.
trx_serialise(): Renamed from trx_serialisation_number_get().
trx_write_serialisation_history(): Simplify the code flow.
If there are no persistent changes, do not update MONITOR_TRX_COMMIT_UNDO.
trx_commit_in_memory(): Simplify the logic, and add assertions.
trx_undo_page_report_modify(): Keep a direct reference to the
persistent update_undo log.
trx_undo_report_row_operation(): Simplify some code.
Always assign TRX_UNDO_INSERT for temporary undo logs.
trx_prepare_low(): Keep only one parameter. Prepare all 3 undo logs.
trx_roll_try_truncate(): Remove the parameter undo_ptr.
Try to truncate all 3 undo logs of the transaction.
trx_roll_pop_top_rec_of_trx_low(): Remove.
trx_roll_pop_top_rec_of_trx(): Remove the redundant parameter
trx->roll_limit. Clear roll_limit when exhausting the undo logs.
Consider all 3 undo logs at once, prioritizing the persistent
undo logs.
row_undo(): Minor cleanup. Let trx_roll_pop_top_rec_of_trx()
reset the trx->roll_limit.
InnoDB undo logs currently always use the innodb_page_size,
whether they are stored in the system tablespace, in a
dedicated undo tablespace, or in the temporary tablespace.
Remove redundant page_size parameters.
TrxUndoRsegsIterator::set_next(): return bool instead of page_size.
In MySQL 5.7, there is some redundant code for supposedly handling
an upgrade from an earlier version of InnoDB.
An upgrade of InnoDB between major versions should include a
slow shutdown (innodb_fast_shutdown=0) of the previous version.
A comment in trx_lists_init_at_db_start() confused clean shutdown
and slow shutdown. A clean shutdown does not necessarily guarantee
that there are no active transactions. A slow shutdown guarantees
that.
Because there was no code to handle rollback of recovered transactions
that happened to use the rollback segment slots that MySQL 5.7.2
repurposed for temporary undo logs, the upgrade is not working in all
cases, and we may as well remove the code to handle purging.
trx_sys_t::pending_purge_rseg_array: Remove.
trx_undo_get_undo_rec_low(): Define as static. Remove the parameter
is_redo_rseg.
trx_undo_get_undo_rec(), trx_rseg_get_on_id(): Remove the parameter
is_redo_rseg.
trx_rseg_mem_free(): Remove the second parameter.
trx_sys_get_nth_rseg(): Replace with trx_rseg_get_on_id().
trx_rseg_schedule_pending_purge(): Remove.
InnoDB keeps track of buffer-fixed buf_block_t or acquired rw_lock_t
within a mini-transaction. There are some memo_contains assertions
in the code that document when certain blocks or rw_locks must be held.
But, these assertions only check the mini-transaction memo, not the fact
whether the rw_lock_t are actually being held by the caller.
btr_pcur_store_position(): Remove #ifdef, and assert that the block
is always buffer-fixed.
rtr_pcur_getnext_from_path(), rtr_pcur_open_low(),
ibuf_rec_get_page_no_func(), ibuf_rec_get_space_func(),
ibuf_rec_get_info_func(), ibuf_rec_get_op_type_func(),
ibuf_build_entry_from_ibuf_rec_func(), ibuf_rec_get_volume_func(),
ibuf_get_merge_page_nos_func(), ibuf_get_volume_buffered_count_func()
ibuf_get_entry_counter_low_func(), page_set_ssn_id(),
row_vers_old_has_index_entry(), row_vers_build_for_consistent_read(),
row_vers_build_for_semi_consistent_read(),
trx_undo_prev_version_build():
Make use of mtr_memo_contains_page_flagged().
mtr_t::memo_contains(): Take a const memo. Assert rw_lock_own().
FindPage, FlaggedCheck: Assert rw_lock_own_flagged().
The InnoDB source code contains quite a few references to a closed-source
hot backup tool which was originally called InnoDB Hot Backup (ibbackup)
and later incorporated in MySQL Enterprise Backup.
The open source backup tool XtraBackup uses the full database for recovery.
So, the references to UNIV_HOTBACKUP are only cluttering the source code.
Contains also:
MDEV-10549 mysqld: sql/handler.cc:2692: int handler::ha_index_first(uchar*): Assertion `table_share->tmp_table != NO_TMP_TABLE || m_lock_type != 2' failed. (branch bb-10.2-jan)
Unlike MySQL, InnoDB still uses THR_LOCK in MariaDB
MDEV-10548 Some of the debug sync waits do not work with InnoDB 5.7 (branch bb-10.2-jan)
enable tests that were fixed in MDEV-10549
MDEV-10548 Some of the debug sync waits do not work with InnoDB 5.7 (branch bb-10.2-jan)
fix main.innodb_mysql_sync - re-enable online alter for partitioned innodb tables
Contains also
MDEV-10547: Test multi_update_innodb fails with InnoDB 5.7
The failure happened because 5.7 has changed the signature of
the bool handler::primary_key_is_clustered() const
virtual function ("const" was added). InnoDB was using the old
signature which caused the function not to be used.
MDEV-10550: Parallel replication lock waits/deadlock handling does not work with InnoDB 5.7
Fixed mutexing problem on lock_trx_handle_wait. Note that
rpl_parallel and rpl_optimistic_parallel tests still
fail.
MDEV-10156 : Group commit tests fail on 10.2 InnoDB (branch bb-10.2-jan)
Reason: incorrect merge
MDEV-10550: Parallel replication can't sync with master in InnoDB 5.7 (branch bb-10.2-jan)
Reason: incorrect merge
Merge Facebook commit 154c579b828a60722a7d9477fc61868c07453d08
and e8f0052f9b112dc786bf9b957ed5b16a5749f7fd authored
by Steaphan Greene from https://github.com/facebook/mysql-5.6
Optimize prefix index queries to skip cluster index lookup when possible.
Currently InnoDB will always fetch the clustered index (primary key
index) for all prefix columns in an index, even when the value of a
particular record is smaller than the prefix length. This change
optimizes that case to use the record from the secondary index and avoid
the extra lookup.
Also adds two status vars that track how effective this is:
innodb_secondary_index_triggered_cluster_reads:
Times secondary index lookup triggered cluster lookup.
innodb_secondary_index_triggered_cluster_reads_avoided:
Times prefix optimization avoided triggering cluster lookup.
Merge Facebook commit 25295d003cb0c17aa8fb756523923c77250b3294
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
This adds a pointer to the trx to each mtr.
This allows the trx to be accessed in parts of the code
where it was otherwise not available. This is needed later.
