This commit merely adds is a Read-Committed version MDEV-30225 test
solely to prove the RC isolation yields ROW binlog format as it is
supposed to per docs.
Problem:
=======
Mysqlbinlog cannot show the type of a compressed
column when two levels of verbosity is provided.
Solution:
========
Extend the log event printing logic to handle and
tag compressed types.
Behavioral Changes:
==================
Old: When mysqlbinlog is called in verbose mode and
the database uses compressed columns, an error is
returned to the user.
New: The output will append “ COMPRESSED” on the
type of compressed columns
Reviewed By
===========
Andrei Elkin <andrei.elkin@mariadb.com>
Problem:
=======
This patch addresses two issues:
1. An incident event can be incorrectly reported for transactions
which are rolled back successfully. That is, an incident event
should only be generated for failed “non-transactional transactions”
(i.e., those which modify non-transactional tables) because they
cannot be rolled back.
2. When the mariadb slave (error) stops at receiving the incident
event there's no description of what led to it. Neither in the event
nor in the master's error log.
Solution:
========
Before reporting an incident event for a transaction, first validate
that it is “non-transactional” (i.e. cannot be safely rolled back).
To determine if a transaction is non-transactional,
lex->stmt_accessed_table(LEX::STMT_WRITES_NON_TRANS_TABLE)
is used because it is set previously in
THD::decide_logging_format().
Additionally, when an incident event is written, write an error
message to the server’s error log to indicate the underlying issue.
Reviewed by:
===========
Andrei Elkin <andrei.elkin@mariadb.com>
* FreeBSD returns errno 31 (EMLINK, Too many links),
not 40 (ELOOP, Too many levels of symbolic links)
* (`mysqlbinlog|mysql`) was just crazy, why did it ever work?
* socket_ipv6.inc check (that checked whether ipv6 is supported)
only worked correctly when ipv6 was supported
* perfschema.socket_summary_by_instance was changing global variables
and then skip-ing the test (because on missing ipv6)
Problem:
========
When the mysql.gtid_slave_pos table uses the InnoDB engine, and
mysqld starts, it reads the table and begins a transaction. After
reading the value, it should end the transaction and release all
associated locks. The bug reported in DBAAS-7828 shows that when
autocommit is off, the locks are not released, resulting in
indefinite hangs on future attempts to change gtid_slave_pos. In
particular, the transaction was not properly finalized because
thd->server_status was not updated to reflect the end of the
transaction.
Solution:
========
This patch updates the code to properly commit the transaction after
reading gtid_slave_pos during mysqld start-up.
Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>
Problem:
========
When using mariadb-binlog with --raw and --stop-never, events from
the master's currently active log file should be written to their
respective log file specified by --result-file, and shown on-disk.
There is a bug where mariadb-binlog does not flush the result file
to disk when new events are received
Solution:
========
Add a function call to flush mariadb-binlog’s result file after
receiving an event in --raw mode.
Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>
The first step for deprecating innodb_autoinc_lock_mode(see MDEV-27844) is:
- to switch statement binlog format to ROW if binlog format is MIXED and
the statement changes autoincremented fields
- issue warnings if innodb_autoinc_lock_mode == 2 and binlog format is
STATEMENT
The warning out of OPTIMIZE
Statement is unsafe because it uses a system function
was indeed counterfactual and was resulted by checking an
insufficiently strict property of lex' sql_command_flags.
Fixed with deploying an additional checking of weather
the current sql command that modifes a share->non_determinstic_insert
table is capable of generating ROW format events.
The extra check rules out the unsafety to OPTIMIZE et al, while the
existing check continues to do so to CREATE TABLE (which is
perculiarly tagged as ROW-event generative sql command).
As a side effect sql_sequence.binlog test gets corrected and
binlog_stm_unsafe_warning.test is reinforced to add up
an unsafe CREATE..SELECT test.
The assert was caused by an error of XA transaction that had
BINLOG 'base64_string' statement.
The statement failed because of lack of checking whether the encoded
replication event was handled by the slave applier thread.
If it's not the slave applier no error should be generated, but it was
in this case, see a test added.
Fixed along with the idea borrowed the upstream to introduce a check
of which applier executes the replication event and do not
report any error if the applier is a regular server client.
CREATE-OR-REPLACE SEQUENCE is not logged with Gtid event DDL flag
which affects its slave parallel execution.
Unlike other DDL:s it can occur in concurrent execution with following transactions
which can lead to various errors, including asserts like
(mdl_request->type != MDL_INTENTION_EXCLUSIVE && mdl_request->type != MDL_EXCLUSIVE) || !(get_thd()->rgi_slave && get_thd()->rgi_slave->is_parallel_exec && lock->check_if_conflicting_replication_locks(this)
in MDL_context::acquire_lock.
Fixed to wrap internal statement level commit with save-
and-restore of TRANS_THD::m_unsafe_rollback_flags.
failed in Diagnostics_area::set_ok_status in my_ok from
mysql_sql_stmt_prepare
Analysis: Before PREPARE is executed, binlog_format is STATEMENT.
This PREPARE had SET STATEMENT which sets binlog_format to ROW. Now after
PREPARE is done we reset the binlog_format (back to STATEMENT). But we have
temporary table, it doesn't let changing binlog_format=ROW to
binlog_format=STATEMENT and gives error which goes unreported. This
unreported error eventually causes assertion failure.
Fix: Change return type for LEX::restore_set_statement_var() to bool and
make it return error state.
Problem:
=======
There are two issues that are addressed in this patch:
1) SHOW BINARY LOGS uses caching to store the binary logs that exist
in the log directory; however, if new events are written to the logs,
the caching strategy is unaware. This is okay for users, as it is
okay for SHOW to return slightly old data. The test, however, can
result in inconsistent data. It runs two connections concurrently,
where one shows the logs, and the other adds a new file. The output
of SHOW BINARY LOGS then depends on when the cache is built, with
respect to the time that the second connection rotates the logs.
2) There is a race condition between RESET MASTER and SHOW BINARY
LOGS. More specifically, where they both need the binary log lock to
begin, SHOW BINARY LOGS only needs the lock to build its cache. If
RESET MASTER is issued after SHOW BINARY LOGS has built its cache and
before it has returned the results, the presented data may be
incorrect.
Solution:
========
1) As it is okay for users to see stale data, to make the test
consistent, use DEBUG_SYNC to force the race condition (problem 2) to
make SHOW BINARY LOGS build a cache before RESET MASTER is called.
Then, use additional logic from the next part of the solution to
rebuild the cache.
2) Use an Atomic_counter to keep track of the number of times RESET
MASTER has been called. If the value of the counter changes after
building the cache, the cache should be rebuilt and the analysis
should be restarted.
Reviewed By:
============
Andrei Elkin: <andrei.elkin@mariadb.com>
Problem:
========
Aborting OPTIMIZE TABLE still logs in binary logs and replicates to the
Slave server. "Optimize table" command under execution, is killed by using
"Ctrl-C" as shown below.
MariaDB [test]> optimize table t2;
^CCtrl-C -- query killed. Continuing normally.
In spite of query execution being interrupted the query gets written to
binary log.
Analysis:
========
Admin command execution logic is not handling KILL command, hence it
ignores the KILL command and completes its execution.
Fix:
===
Check for thread killed notification, during admin command execution and
handle it. If thread kill occurs prior to any table modification the query
will not be written to binary log. If kill happens after at least one table
is modified then the query will be written to binary log. Ex: command in
execution is 'OPTIMIZE TABLE t1,t2' and the thread kill happens after t1
table is modified then 'OPTIMIZE TABLE t1,t2' will be written to binary log
as admin commands will not make the slave to diverge from master.
There was race between a committing transaction and the following in binlog
order FLUSH LOGS that could create a 2nd Binlog checkpoint (BCP) event
in the new file *before* the first logged-in-old-binlog transaction gets committed in
Innodb. That would cause the transaction loss at recovery, should
the server stop right after the BCP.
The race is tackled by enforcing the necessary set of mutexes to be acquired
by FLUSH-LOGS handler in the correct order (of the group commit leader
pattern).
Note, there remain two cases where a similar race is still possible:
- the above race as it is when the server is run with ("unlikely")
non-default `--binlog-optimize-thread-scheduling=0` (MDEV-24530), and
- at unlikely event of bin-logging of Incident event (MDEV-24531) that
also triggers binlog rotation,
in both cases though with lesser chances after the current fixes.
