post-merge fixes:
* remove log_slow_queries_not_using_indexes, no need to create variables
that are deprecated since the moment of creation
* rename log_slow_query_enable->log_slow_query
no other variable uses *_enable pattern
* MDEV-29626 Assertion `self == &Sys_slow_query_log' failed in fix_log_state
* tests
Closes#2137
There are separate flags DBUG_OFF for disabling the DBUG facility
and ENABLED_DEBUG_SYNC for enabling the DEBUG_SYNC facility.
Let us allow debug builds without DEBUG_SYNC.
Note: For CMAKE_BUILD_TYPE=Debug, CMakeLists.txt will continue to
define ENABLED_DEBUG_SYNC.
this test loads sql_errlog plugin. then in a second connection
it triggers an error, this locks the plugin in that thd.
then the plugin is uninstalled in the default connection.
but that doesn't unload the plugin, as it's still locked. it'll
auto-unload after the foo connection is closed. without an explicit
disconnect it is closed after mysqltest exits and the post-test check
might still see sql_errlog not fully unoaded.
Test fixes:
Since fix for CONC-603 (wrong error handling in TLS read/write) in case
of a read/write error client doesn't return always error 2013 (server
has gone away), so in addition we need to check for error 2026
(TLS/SSL error) and 5014 (write error).
MDEV-28073 Slow query performance in MariaDB when using many table
The idea is to prefer and chain EQ_REF tables (tables that uses an
unique key to find a row) when searching for the best table combination.
This significantly reduces row combinations that has to be examined.
This is optimization is enabled when setting optimizer_prune_level=2
(which is now default).
Implementation:
- optimizer_prune_level has a new level, 2, which enables EQ_REF
optimization in addition to the pruning done by level 1.
Level 2 is now default.
- Added JOIN::eq_ref_tables that contains bits of tables that could use
potentially use EQ_REF access in the query. This is calculated
in sort_and_filter_keyuse()
Under optimizer_prune_level=2:
- When the greedy_optimizer notices that the preceding table was an
EQ_REF table, it tries to add an EQ_REF table next. If an EQ_REF
table exists, only this one will be considered at this level.
We also collect all EQ_REF tables chained by the next levels and these
are ignored on the starting level as we have already examined these.
If no EQ_REF table exists, we continue as normal.
This optimization speeds up the greedy_optimizer combination test with
~25%
Other things:
- I ported the changes in MySQL 5.7 to greedy_optimizer.test to MariaDB
to be able to ensure we can handle all cases that MySQL can do.
- I have run all tests with --mysqld=--optimizer_prune_level=1 to verify that
there where no test changes.
These system variables:
@@character_set_client
@@character_set_connection
@@character_set_database
@@character_set_filesystem
@@character_set_results
@@character_set_server
can now be set in numeric format only to IDs of default collations, e.g.:
SET @@character_set_xxx=9; -- OK (latin2_general_ci is default)
SET @@character_set_xxx=2; -- ERROR (latin2_czech_cs is not default)
SET @@character_set_xxx=21; -- ERROR (latin2_hungarian_ci is not default)
Before this change the server accepted IDs of non-default collations
so all three examples above worked without errors,
but this could lead to unexpected behavior in later statements.
In commit c4c8830709 (MDEV-28111) we disabled
the file system cache on the InnoDB write-ahead log file (ib_logfile0)
by default on Linux.
It turns out that especially with innodb_flush_trx_log_at_commit=2,
writing to the log via the file system cache typically improves throughput,
especially on slow storage or at a small number of concurrent transactions.
For other values of innodb_flush_log_at_trx_commit, direct writes were
observed to be mostly but not always faster. Whether it pays off to
disable the file system cache on the log may depend on the type of storage,
the workload, and the operating system kernel version.
On Linux and Microsoft Windows, we will introduce the settable Boolean
global variable innodb_log_file_buffering that indicates whether the
file system cache on the redo log file is enabled. The default value is
innodb_log_file_buffering=OFF. If the server is started up with
innodb_flush_log_at_trx_commit=2, the value will be changed to
innodb_log_file_buffering=ON.
When a persistent memory interface is being used for the log,
the value cannot be changed from innodb_log_file_buffering=OFF.
On Linux, when the physical block size cannot be determined
to be a power of 2 between 64 and 4096 bytes, the file system cache
cannot be disabled, and innodb_log_file_buffering=ON cannot be changed.
Server log messages will indicate whether the file system cache is
enabled for the redo log:
[Note] InnoDB: Buffered log writes (block size=512 bytes)
[Note] InnoDB: File system buffers for log disabled (block size=512 bytes)
After this change, the startup parameter innodb_flush_method will no
longer control whether O_DIRECT will be set on the redo log on Linux.
On other operating systems that support O_DIRECT, no interface has been
implemented for controlling the file system cache for the redo log.
The innodb_flush_method values O_DIRECT, O_DIRECT_NO_FSYNC, O_DSYNC
will enable O_DIRECT for data files, not the log.
Tested by: Matthias Leich, Axel Schwenke
The parameter innodb_prefix_index_cluster_optimization used to enable an
optimization that was added in cb37c55768
and was disabled by default.
We will unconditionally enable the extension and mark the parameter
as deprecated.
Related to this, the counters
Innodb_secondary_index_triggered_cluster_reads and
Innodb_secondary_index_triggered_cluster_reads_avoided
allowed to determine the usefulness of this optimization.
Now that the configuration parameter is disabled, the counters
do not serve any useful purpose and can be removed.
row_search_with_covering_prefix(): Fix a bug that caused an
incorrect result to be returned.
INNODB_VERSION_STR: Replaced with PACKAGE_VERSION (non-functional change).
INNODB_VERSION_SHORT: Replaced with direct use of
MYSQL_VERSION_MAJOR << 8 | MYSQL_VERSION_MINOR.
check_version(): Simplify the mariadb-backup version check,
and require the server version to be MariaDB 10.8 or later,
because that is when the InnoDB redo log format was last changed.
InnoDB buffer pool resize messages are more succinct from this change:
Before:
```
2022-05-07 17:10:33 0 [Note] InnoDB: Completed resizing buffer pool from 14745600 to 19660800 bytes.
2022-05-07 17:10:33 0 [Note] InnoDB: Completed resizing buffer pool.
2022-05-07 17:10:33 8 [Note] InnoDB: Completed resizing buffer pool. (New size: 19660800 bytes).
```
After:
```
2022-05-07 17:10:33 0 [Note] InnoDB: Completed resizing buffer pool from 14745600 to 19660800 bytes.
```
Additionally, the INNODB_BUFFER_POOL_RESIZE_STATUS has more complete
info: it contains both the old and new buffer pool size values.
