Problem:
=======
In slave_parallel_mode=optimistic configuration, when admin commands and
DML operation on the same table are scheduled simultaneously for execution,
it results in lock conflict and slave server either hangs due to
deadlock or goes down with an assert.
Analysis:
========
Admin commands OPTIMIZE, REPAIR and ANALYZE are written to binary log as
ordinary transactions. When 'slave_parallel_mode' is 'optimistic' DMLs are
allowed to run in parallel. But these locks are not detected by parallel
replication deadlock detection-and-handling mechanism. At times they result
in deadlock or assertion.
Fix:
===
Flag admin commands as DDL in Gtid_log_event at the time of writing to
binary log. Add a new bit EXECUTED_TABLE_ADMIN_CMD to
'm_unsafe_rollback_flags'. During 'mysql_admin_table' command execution it
accepts a list of tables to be processed and executes them in a loop. Upon
successful execution enable 'EXECUTED_TABLE_ADMIN_CMD' bit in
thd->transaction.stmt_unsafe_rollback_flags. Gtid_log_event constructor
will notice this flag and mark the current transaction with 'FL_DDL' flag.
Gtid_log_events marked as FL_DDL will not be scheduled parallel execution,
on the slave. They will execute in isolation to prevent deadlocks.
Note: Removed the call to 'trans_commit_implicit' from 'mysql_admin_table'
function as 'mysql_execute_command' will take care of invoking
'trans_commit_implicit'.
- row_search_mvcc() should return DB_INTERRUPTED when it got killed.
- Add a syncpoint for the ICP check.
- Add test coverage for killed-during-ICP-check scenario
Backport of MDEV-22761 fixes for ICP from 10.4 commits:
* a6f956488c
* c03885cd9c
XtraDB was fixed in deb3b9a174
Reviewer: Daniel Black
1. rr record -h randomizes number of processors. Disable THREAD_POOL_SIZE check.
2. check for kernel.perf_event_paranoid for user-friendly error message.
The InnoDB index fields store bytes, not characters.
Remove some unnecessary conversions from characters to bytes.
This also fixes MDEV-20422 and the wrong-result bug MDEV-12486.
Shutdown of mtr tests may be too impatient, esp on CI environment where
10 seconds of `arg` of `shutdown_server arg` may not be enough for the clean
shutdown to complete.
This is fixed to remove explicit non-zero timeout argument to
`shutdown_server` from all mtr tests. mysqltest computes 60 seconds default
value for the timeout for the argless `shutdown_server` command.
This policy is additionally ensured with a compile time assert.
Problem:
========
During point in time recovery of binary log syntax error is reported for
BEGIN statement and recovery fails.
Analysis:
=========
In MariaDB 10.3 and later, setting the sql_mode system variable to Oracle
allows the server to understand a subset of Oracle's PL/SQL language. When
sql_mode=ORACLE is set, it switches the parser from the MariaDB parser to
Oracle compatible parser. With this change 'BEGIN' is not considered as
'START TRANSACTION'. Hence the syntax error is reported.
Fix:
===
At preset 'BEGIN' query is generated from 'Gtid_log_event::print'. The current
session specific 'sql_mode' information is not present as part of
'Gtid_log_event'. If it was available then, mysqlbinlog tool can make use of
'sql_mode == ORACLE' and can output "START TRANSACTION" in this particular
mode and for other sql_modes it will write "BEGIN" as part of output. Since it
is not available 'mysqlbinlog' tool will output all 'BEGIN' statements as
'START TRANSACTION' irrespective of 'sql_mode'.
For DECIMAL[(M[,D])] datatype max_sort_length was not being honoured which was leading to buffer
overflow while making the sort key. The fix to this problem would be to create sort keys for decimals
with atmost max_sort_key bytes
Important:
The minimum value of max_sort_length has been raised to 8 (previously was 4),
so fixed size datatypes like DOUBLE and BIGINIT are not truncated for
lower values of max_sort_length.
Fixed a couple of race conditions in the test case to ensure stable order
of events. Also removed all sleeps. Test execution time is down from 18s
to 0.15s.
On disconnect audit event is triggered after control is returned to
mysqltest client. Which means mysqltest may issue more commands
concurrently before disconnect is actually logged.
Similar problem happens with regular query execution: an event is
triggered after control is returner to the client. Which may end
up with unstable order of events in different connections.
Delayed insert rows are enqueued separately and can either be combined
into single event or go as separate events. Reduced number of inserted
rows to 1 to stabilize result.
Also backported 2b3f6ab from 10.5.
join_cache_level=6+
The patch fixes two similar bugs in the commit 8eeb689e9f
that added multi_range_read support to partitions. The commit opened
a possibility to join a partition table using BKA+MRR. However in some
cases it could lead to wrong results or even crashes.
This could happened when
- index condition pushdown was used to join the table or
- the joined table was an inner table of an outer join and 'not exist'
optimization was applied or
- the join table was the inner table of a semi-join and the first match
optimization was applied
The bugs were in the code of the call-back functions
- partition_multi_range_key_skip_record() and
- partition_multi_range_key_skip_index_tuple().
Each of this function consist only of an invocation of another function.
Yet a wrong parameter was passed at this invocation.
The fix was suggested by Sergey Petrunia and it is apparently in line
with original design.
The corresponding comprehensive test cases demonstrating the problems
caused by the bugs were constructed by me.
Problem:
=======
Test "binlog.binlog_parallel_replication_marks_row" fails sporadically due to
result length mismatch.
Analysis:
=========
Test generates a binary log and it looks for certain words within the binary
log file and prints them. For example word like "GTID,BEGIN,COMMIT ...".
Binary log output contains base64 encoded characters. Occasionally the encoded
characters match with the above words and results in test failure.
+XwoFWxMBAAAALgAAAGEDAAAAAB8AAAAAAAEABHRlc3QAAnQxAAIDAwACFGTIDQ==
+AAAAAAAAAAAEEwQADQgICAoKCgGTIDw9
Fix:
===
Improve the regular expression to match exact words.
Fix partitioning and DS-MRR to work together
- In ha_partition::index_end(): take into account that ha_innobase (and
other engines using DS-MRR) will have inited=RND when initialized for
DS-MRR scan.
- In ha_partition::multi_range_read_next(): if the MRR scan is using
HA_MRR_NO_ASSOCIATION mode, it is not guaranteed that the partition's
handler will store anything into *range_info.
- In DsMrr_impl::choose_mrr_impl(): ha_partition will inquire partitions
about how much memory their MRR implementation needs by passing
*buffer_size=0. DS-MRR code didn't know about this (actually it used
uint for buffer size calculation and would have an under-flow).
Returning *buffer_size=0 made ha_partition assume that partitions do
not need MRR memory and pass the same buffer to each of them.
Now, this is fixed. If DS-MRR gets *buffer_size=0, it will return
the amount of buffer space needed, but not more than about
@@mrr_buffer_size.
* Fix ha_{innobase,maria,myisam}::clone. If ha_partition uses MRR on its
partitions, and partition use DS-MRR, the code will call handler->clone
with TABLE (*NOT partition*) name as an argument.
DS-MRR has no way of knowing the partition name, so the solution was
to have the ::clone() function for the affected storage engine to ignore
the name argument and get it elsewhere.
The test main.index_merge_innodb is taking very much time,
especially on later versions (10.2 and 10.3).
Some of this could be attributed to the use of INSERT...SELECT,
which is time-consumingly creating explicit record locks in InnoDB
for the locking read in the SELECT part.
In 10.3 and later, some slowness can be attributed to MDEV-12288,
which makes the InnoDB purge thread spend time to reset transaction
identifiers in the inserted records. If we prevent purge from
running before all tables are dropped, the test seems to be
10% faster on an unoptimized debug build on 10.5. (A proper fix
would be to implement MDEV-515 and stop writing row-level undo log
records for inserts into an empty table or partition.)
At the same time, it should not hurt to make main.index_merge_myisam
to use the sequence engine. Not only could it be a little faster,
but the test would be slightly more readable.
MDEV-20589: Server still crashes in Field::set_warning_truncated_wrong_value
- Use dbug_tmp_use_all_columns() to mark that all fields can be used
- Remove field->is_stat_field (not needed)
- Remove extra arguments to Field::clone() that should not be there
- Safety fix for Field::set_warning_truncated_wrong_value() to not crash
if table is zero in production builds (We have got crashes several times
here so better to be safe than sorry).
- Threat wrong character string warnings identical to other field
conversion warnings. This removes some warnings we before got from
internal conversion errors. There is no good reason why a user would
get an error in case of 'key_field='wrong-utf8-string' but not for
'field=wrong-utf8-string'. The old code could also easily give
thousands of no-sence warnings for one single statement.
This allows one to run the test suite even if any of the following
options are changed:
- character-set-server
- collation-server
- join-cache-level
- log-basename
- max-allowed-packet
- optimizer-switch
- query-cache-size and query-cache-type
- skip-name-resolve
- table-definition-cache
- table-open-cache
- Some innodb options
etc
Changes:
- Don't print out the value of system variables as one can't depend on
them to being constants.
- Don't set global variables to 'default' as the default may not
be the same as the test was started with if there was an additional
option file. Instead save original value and reset it at end of test.
- Test that depends on the latin1 character set should include
default_charset.inc or set the character set to latin1
- Test that depends on the original optimizer switch, should include
default_optimizer_switch.inc
- Test that depends on the value of a specific system variable should
set it in the test (like optimizer_use_condition_selectivity)
- Split subselect3.test into subselect3.test and subselect3.inc to
make it easier to set and reset system variables.
- Added .opt files for test that required specfic options that could
be changed by external configuration files.
- Fixed result files in rockdsb & tokudb that had not been updated for
a while.
- mysqltest didn't free read_command_buf
- wait_for_slave_param did write different things to the log if valgrind
was used.
- Table open cache should not write the initial variable value as it
can depend on the configuration or if valgrind is used
- A variable in GetResult was used uninitalized
MDEV-5589 commit set up a policy to skip DROP TEMPORARY TABLE binary logging
in case the target table has not been "CREATEed" in binlog (no CREATE
Query-log-event was logged into the binary log).
It turns out that
1. the rule did not cover non-existing table DROPped with IF-EXISTS clause.
The logged-create knowledge for the non-existing one does not even need
MDEV-5589 patch, and
2. connection close disobeys it to trigger automatic DROP-IF-EXISTS
binlogging.
Either 1 or 2 or even both is/are also responsible for unexpected binlog
records observed in MDEV-17863, actually rendering a referred
@@global.read_only irrelevant as far as the described stored procedure
definition *and* the ROW binlog-format are concerned.
Currently, running mtr with an incorrect (for example, new or
obsolete) version of wsrep_provider (for example, with the 26
version of libgalera_smm.so) leads to the failure of tests in
several suites with vague error diagnostics.
As for the galera_3nodes suite, the mtr also does not effectively
check all the prerequisites after merge with MDEV-18426 fixes.
For example, tests that using mariabackup do not check for presence
of ss and socat/nc. This is due to improper handling of relative
paths in mtr scripts.
In addition, some tests in different suites can be run without
setting the environment variables such as MTR_GALERA_TFMT, XBSTREAM,
and so on.
To eliminate all these issues, this patch makes the following changes:
1. Added auxiliary wsrep_mtr_check utility (which located in the
mysql-test/lib/My/SafeProcess subdirectory), which compares the
versions of the wsrep API that used by the server and by the wsrep
provider library, and it does this comparison safely, without
accessing the API if the versions do not match.
2. All checks related to the presence of mariabackup and utilities
that necessary for its operation transferred from the local directories
of different mtr suites (from the suite.pm files) to the main suite.pm
file. This not only reduces the amount of code and eliminates duplication
of identical code fragments, but also avoids problems due to the inability
of mtr to consider relative paths to include files when checking skip
combinations.
3. Setting the values of auxiliary environment variables that
are necessary for Galera, SST scripts and mariabackup (to work
properly) is moved to the main mysql-test-run.pl script, so as
not to duplicate this code in different suites, and to avoid
partial corrections of the same errors for different suites
(while other suites remain uncorrected).
4. Fixed duplication of the have_file_key_management.inc and
have_filekeymanagement.inc files between different suites,
these checks are also transferred to the top level.
5. Added garbd presence check and garbd path variable.
https://jira.mariadb.org/browse/MDEV-18565