MDEV-27025 allows to insert records before the record on which DELETE is
locked, as a result the DELETE misses those records, what causes serious ACID
violation.
Revert MDEV-27025, MDEV-27550. The test which shows the scenario of ACID
violation is added.
btr_cur_optimistic_insert(): Disregard DEBUG_DBUG injection to
invoke btr_page_reorganize() if the page (and the table) is empty.
Otherwise, an assertion would fail in btr_page_reorganize_low()
because PAGE_MAX_TRX_ID is 0 in an empty secondary index leaf page.
Backported from 10.5 20e9e804c1 and
5948d7602e.
sel_restore_position_for_mysql() moves forward persistent cursor
position after btr_pcur_restore_position() call if cursor relative position
is BTR_PCUR_ON and the cursor points to the record with NOT the same field
values as in a stored record(and some other not important for this case
conditions).
It was done because btr_pcur_restore_position() sets
page_cur_mode_t mode to PAGE_CUR_LE for cursor->rel_pos == BTR_PCUR_ON
before opening cursor. So we are searching for the record less or equal
to stored one. And if the found record is not equal to stored one, then
it is less and we need to move cursor forward.
But there can be a situation when the stored record was purged, but the
new one with the same key but different value was inserted while
row_search_mvcc() was suspended. In this case, when the thread is
awaken, it will invoke sel_restore_position_for_mysql(), which, in turns,
invoke btr_pcur_restore_position(), which will return false because found
record don't match stored record, and
sel_restore_position_for_mysql() will move forward cursor position.
The above can lead to the case when awaken row_search_mvcc() do not see
records inserted by other transactions while it slept. The mtr test case
shows the example how it can be.
The fix is to return special value from persistent cursor restoring
function which would notify its caller that uniq fields of restored
record and stored record are the same, and in this case
sel_restore_position_for_mysql() don't move cursor forward.
Delete-marked records are correctly processed in row_search_mvcc().
Non-unique secondary indexes are "uniquified" by adding the PK, the
index->n_uniq should then be index->n_fields. So there is no need in
additional checks in the fix.
If transaction's readview can't see the changes made in secondary index
record, it requests clustered index record in row_search_mvcc() to check
its transaction id and get the correspondent record version. After this
row_search_mvcc() commits mtr to preserve clustered index latching
order, and starts mtr. Between those mtr commit and start secondary
index pages are unlatched, and purge has the ability to remove stored in
the cursor record, what causes rows duplication in result set for
non-locking reads, as cursor position is restored to the previously
visited record.
To solve this the changes are just switched off for non-locking reads,
it's quite simple solution, besides the changes don't make sense for
non-locking reads.
The more complex and effective from performance perspective solution is
to create mtr savepoint before clustered record requesting and rolling
back to that savepoint after that. See MDEV-27557.
One more solution is to have per-record transaction id for secondary
indexes. See MDEV-17598.
If any of those is implemented, just remove select_lock_type argument in
sel_restore_position_for_mysql().
convert_error_code_to_mysql(): Use the correct limit FK_MAX_CASCADE_DEL
in the error message. The DICT_FK_MAX_RECURSIVE_LOAD applies to
the number of foreign key constraints in table definitions,
not to the number of rows that are visited while processing
a foreign key constraint.
Some GNU/Linux distributions ship a zlib that is modified to use
the s390x DFLTCC instruction. That modification would essentially
redefine compressBound(sourceLen) as (sourceLen * 16 + 2308) / 8 + 6.
Let us relax the tests for InnoDB ROW_FORMAT=COMPRESSED to cope with
such a weaker compression guarantee.
create_table_info_t::row_size_is_acceptable(): Remove a bogus debug-only
assertion that would fail to hold for the test innodb_zip.bug36169.
The function page_zip_empty_size() may indeed return 0.
row_sel_sec_rec_is_for_clust_rec() treats empty BLOB prefix field in
secondary index as a field equal to any external BLOB field in clustered
index. Row_sel_get_clust_rec_for_mysql::operator() doesn't zerro out
clustered record pointer in row_search_mvcc(), and row_search_mvcc()
thinks that delete-marked secondary index record has visible for
"CHECK TABLE"'s read view old-versioned clustered index record, and
row_scan_index_for_mysql() counts it as a row.
The fix is to execute row_sel_sec_rec_is_for_blob() in
row_sel_sec_rec_is_for_clust_rec() if clustered field contains BLOB's
reference.
Removing DEFAULT from INFORMATION_SCHEMA columns.
DEFAULT in read-only tables is rather meaningless.
Upgrade should go smoothly.
Also fixes:
MDEV-20254 Problems with EMPTY_STRING_IS_NULL and I_S tables
It's misleading to compare and write to user number of columns and fields.
Thus, it would be better to remove that check and let use see a subsequent
error message about missing or mispaced column.
row_import::match_schema(): remove misleading check
The InnoDB DATA DIRECTORY attribute is not implemented via
symbolic links but something similar, *.isl files that contain
the names of data files.
InnoDB failed to ignore the DATA DIRECTORY attribute even though
the server was started with --skip-symbolic-links.
Native ALTER TABLE in InnoDB will retain the DATA DIRECTORY attribute
of the table, no matter if the table will be rebuilt or not.
Generic ALTER TABLE (with ALGORITHM=COPY) as well as TRUNCATE TABLE
will discard the DATA DIRECTORY attribute.
All tests have been run with and without the ./mtr option
--mysqld=--skip-symbolic-links
and some tests that use the InnoDB DATA DIRECTORY attribute
have been adjusted for this.
.. to be the same as startup.
In resolving MDEV-27461, BUF_LRU_MIN_LEN (256) is the minimum number of
pages for the innodb buffer pool size. Obviously we need more than just
flushing pages. Taking the 16k page size and its default minimum, an
extra 25% is needed on top of the flushing pages to make a workable buffer
pool.
The minimum innodb_buffer_pool_chunk_size (1M) restricts the minimum
otherwise we'd have a pool made up of different chunk sizes.
The resulting minimum innodb buffer pool sizes are:
Page Size, Previously minimum (startup), with change.
4k 5M 2M
8k 5M 3M
16k 5M 5M
32k 24M 10M
64k 24M 20M
With this patch, SET GLOBAL innodb_buffer_pool_size minimums are
enforced.
The evident minimum system variable size for innodb_buffer_pool_size
is 2M, however this is only setable if using 4k page size. As
the order of the page_size and buffer_pool_size aren't fixed, we can't
hide this change.
Subsequent changes:
* innodb_buffer_pool_resize_with_chunks.test - raised of pool resize due to new
minimums. Chunk size also needed increase as the test was for
pool_size < chunk_size to generate a warning.
* Removed srv_buf_pool_min_size and replaced use with MYSQL_SYSVAR_NAME(buffer_pool_size).min_val
* Removed srv_buf_pool_def_size and replaced constant defination in
MYSQL_SYSVAR_LONGLONG(buffer_pool_size)
* Reordered ha_innodb to allow for direct use of MYSQL_SYSVAR_NAME(buffer_pool_size).min_val
* Moved buf_pool_size_align into ha_innodb to access to MYSQL_SYSVAR_NAME(buffer_pool_size).min_val
* loose-innodb_disable_resize_buffer_pool_debug is needed in the
innodb.restart.opt test so that under debug mode, resizing of the
innodb buffer pool can occur.
The column INFORMATION_SCHEMA.INNODB_LOCKS.LOCK_DATA
would report NULL when the page that contains the locked
record does not reside in the buffer pool.
Pages may be evicted from the buffer pool due to some background
activity, such as the purge of transaction history loading
undo log pages to the buffer pool. The regression tests intentionally
run with a small buffer pool size setting.
To prevent the intermittent test failures, we will filter out the
contents of the LOCK_DATA column from the output.
Since commit fb335b48b5 we may have
a null pointer in purge_sys.query when fetch_data_into_cache() is
invoked and innodb_force_recovery>4. This is because the call to
purge_sys.create() would be skipped.
fetch_data_into_cache(): Load the purge_sys pseudo transaction pointer
to a local variable (null pointer if purge_sys is not initialized).
create_log_files(): Check log_set_capacity() before modifying
or creating any log files.
innobase_start_or_create_for_mysql(): If create_log_files()
fails and we were initializing a new database, delete the
system tablespace files before exiting.
strmake() puts one extra 0x00 byte at the end of the string.
The code in my_strnxfrm_tis620[_nopad] did not take this into
account, so in the reported scenario the 0x00 byte was put outside
of a stack variable, which made ASAN crash.
This problem is already fixed in in MySQL:
commit 19bd66fe43c41f0bde5f36bc6b455a46693069fb
Author: bin.x.su@oracle.com <>
Date: Fri Apr 4 11:35:27 2014 +0800
But the fix does not seem to be correct, as it breaks when finds a zero byte
in the source string.
Using memcpy() instead of strmake().
- Unlike strmake(), memcpy() it does not write beyond the destination
size passed.
- Unlike the MySQL fix, memcpy() does not break on the first 0x00 byte found
in the source string.
create_table_info_t::innobase_table_flags(): Refuse to create
a PAGE_COMPRESSED table with PAGE_COMPRESSION_LEVEL=0 if also
innodb_compression_level=0.
The parameter value innodb_compression_level=0 was only somewhat
meaningful for testing or debugging ROW_FORMAT=COMPRESSED tables.
For the page_compressed format, it never made any sense, and the
check in dict_tf_is_valid_not_redundant() that was added in
72378a2583 (MDEV-12873) would cause
the server to crash.
On deadlock transaction is rolled back (and trx->state is cleared) but
SELECT continued the loop because evaluate_join_record() ignored the
error status returned from lower join evaluation. val_int() does not
return error status so it is checked by thd->is_error().
Test case was created by Thirunarayanan Balathandayuthapani
<thiru@mariadb.com>
Occasionally, after restart, additional transactions will have been
executed, possibly related to innodb_stats_auto_recalc.
We should only care that the transaction ID sequence does
not go backwards.
Let us mask the actual values of the defragmentation-related fields,
because they may vary. Also, remove the dependency on purge,
and instead delete records by a ROLLBACK of INSERT.
trx_rseg_header_create(): Add a parameter for the value that is
to be written to TRX_RSEG_MAX_TRX_ID. If we omit this write, then
the updated test innodb.undo_truncate will fail for the 4k, 8k, 16k
page sizes. This was broken ever since
commit 947efe17ed (MDEV-15158)
removed the writes of transaction identifiers to the TRX_SYS page.
srv_do_purge(): Truncate undo tablespaces also during slow shutdown
(innodb_fast_shutdown=0).
Thanks to Krunal Bauskar for noticing this problem.
At least since commit 055a3334ad
(MDEV-13564) the undo log truncation in InnoDB did not work correctly.
The main issue is that during the execution of
trx_purge_truncate_history() some pages of the newly truncated
undo tablespace could be discarded.
fsp_try_extend_data_file(): Apply the peculiar rounding of
fil_space_t::size_in_header only to the system tablespace,
whose size can be expressed in megabytes in a configuration parameter.
Other files may freely grow by a number of pages.
fseg_alloc_free_page_low(): Do allow the extension of undo tablespaces,
and mention the file name in the error message.
mtr_t::commit_shrink(): Implement crash-safe shrinking of a tablespace
file. First, durably write the log, then shrink the file, and finally
release the page latches of the rebuilt tablespace. Refactored from
trx_purge_truncate_history().
log_write_and_flush_prepare(), log_write_and_flush(): New functions
to durably write log during mtr_t::commit_shrink().
btr_defragment_save_defrag_stats_if_needed(): Do not save
defragmentation statistics for temporary tables.
They are exempt of defragmentation anyway
(ha_innobase::optimize() never invokes defragmentation for them),
and the user-visible names are not available inside InnoDB.
Furthermore, InnoDB assumes that temporary tables are never accessed
by other threads than the one that handles the session with which
the temporary table is associated with.
Furthermore, we simplify the test innodb.innodb_defrag_stats
and include a test case that demonstrates that defragmentation
statistics are no longer being saved for temporary tables.
The st_blksize returned by fstat(2) is not documented to be
a power of 2, like we assumed in
commit 58252fff15 (MDEV-26040).
While on Linux, the st_blksize appears to report the file system
block size (which hopefully is not smaller than the sector size
of the underlying block device), on FreeBSD we observed
st_blksize values that might have been something similar to st_size.
Also IBM AIX was affected by this. A simple test case would
lead to a crash when using the minimum innodb_buffer_pool_size=5m
on both FreeBSD and AIX:
seq -f 'create table t%g engine=innodb select * from seq_1_to_200000;' \
1 100|mysql test&
seq -f 'create table u%g engine=innodb select * from seq_1_to_200000;' \
1 100|mysql test&
We will fix this by not trusting st_blksize at all, and assuming that
the smallest allowed write size (for O_DIRECT) is 4096 bytes. We hope
that no storage systems with larger block size exist. Anything larger
than 4096 bytes should be unlikely, given that it is the minimum
virtual memory page size of many contemporary processors.
MariaDB Server on Microsoft Windows was not affected by this.
While the 512-byte sector size of the venerable Seagate ST-225 is still
in widespread use, the minimum innodb_page_size is 4096 bytes, and
innodb_log_file_size can be set in integer multiples of 65536 bytes.
The only occasion where InnoDB uses smaller data file block sizes than
4096 bytes is with ROW_FORMAT=COMPRESSED tables with KEY_BLOCK_SIZE=1
or KEY_BLOCK_SIZE=2 (or innodb_page_size=4096). For such tables,
we will from now on preallocate space in integer multiples of 4096 bytes
and let regular writes extend the file by 1024, 2048, or 3072 bytes.
The view INFORMATION_SCHEMA.INNODB_SYS_TABLESPACES.FS_BLOCK_SIZE
should report the raw st_blksize.
For page_compressed tables, the function fil_space_get_block_size()
will map to 512 any st_blksize value that is larger than 4096.
os_file_set_size(): Assume that the file system block size is 4096 bytes,
and only support extending files to integer multiples of 4096 bytes.
fil_space_extend_must_retry(): Round down the preallocation size to
an integer multiple of 4096 bytes.
ha_innobase::check_if_supported_inplace_alter(): Do not invoke
innobase_table_is_empty() if the tablespace has been discarded.
That is, native ALTER TABLE in InnoDB will treat an empty table
in the same way as a tablespace whose tablespace has been discarded.
(Note: ALTER TABLE...ALGORITHM=COPY will fail if the tablespace
has been discarded.)
This fixes a crash that was introduced
in commit c755974775 (MDEV-19611).
If lock type is LOCK_GAP or LOCK_ORDINARY, and the transaction holds
implicit lock for the record, then explicit gap-lock will not be set for
the record, as lock_rec_convert_impl_to_expl() returns true and
lock_rec_convert_impl_to_expl() bypasses lock_rec_lock() call.
The fix converts explicit lock to implicit one if requested lock type is
not LOCK_REC_NOT_GAP.
innodb_information_schema test result is also changed as after the fix
the following statements execution:
SET autocommit=0;
INSERT INTO t1 VALUES (5,10);
SELECT * FROM t1 FOR UPDATE;
leads to additional gap lock requests.
Set tests to non-valgrind:
oqgraph.social
encryption.innodb-page_encryption
binlog_encryption.encrypted_master
innodb.innodb-page_compression_lz4
main.lock_multi_bug38499
main.lock_multi_bug38691
