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author | Marko Mäkelä <marko.makela@mariadb.com> | 2020-10-25 11:48:34 +0200 |
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committer | Marko Mäkelä <marko.makela@mariadb.com> | 2020-10-25 11:48:34 +0200 |
commit | 987df9b37a2198ab70fb12076fa983d2efe408bc (patch) | |
tree | fb45c06be4821c0377ac2635ed5d173ddb3ad8be /mysql-test/suite/sys_vars | |
parent | 4e987b1c6ba7a0d73c5df54ae0af2805c081b0c3 (diff) | |
download | mariadb-git-987df9b37a2198ab70fb12076fa983d2efe408bc.tar.gz |
MDEV-23720 Change innodb_log_optimize_ddl=OFF by default
MariaDB 10.2.2 inherited from MySQL 5.7 a perceived optimization
of ALTER TABLE, which skips the writing of redo log records.
In MDEV-16809 we introduced a parameter that allows the redo log to
be written, so that Mariabackup would not be impacted, but we kept
the MySQL 5.7 behaviour enabled by default (innodb_log_optimize_ddl=ON).
As noted in MDEV-19747 (Deprecate and ignore innodb_log_optimize_ddl,
implemented in MariaDB 10.5.1), omitting the redo log writes can
actually reduce performance, because we will have to wait for the data
pages to be written out. When the redo log file is configured to be
large enough, it actually can be much faster to write the redo log and
avoid the extra page flushing.
When the redo log is omitted (innodb_log_optimize_ddl=ON), also
Mariabackup may have to perform a lot of extra work, to re-copy the
entire data file if it is possible that any log was omitted during
the backup.
Starting with MariaDB 10.5.1, the parameter innodb_log_optimize_ddl
is deprecated and ignored. We hereby deprecate (but will not ignore)
the parameter in earlier versions as well.
Diffstat (limited to 'mysql-test/suite/sys_vars')
-rw-r--r-- | mysql-test/suite/sys_vars/r/sysvars_innodb.result | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mysql-test/suite/sys_vars/r/sysvars_innodb.result b/mysql-test/suite/sys_vars/r/sysvars_innodb.result index bed23a777a8..d3d30f8f53f 100644 --- a/mysql-test/suite/sys_vars/r/sysvars_innodb.result +++ b/mysql-test/suite/sys_vars/r/sysvars_innodb.result @@ -1568,10 +1568,10 @@ READ_ONLY YES COMMAND_LINE_ARGUMENT REQUIRED VARIABLE_NAME INNODB_LOG_OPTIMIZE_DDL SESSION_VALUE NULL -DEFAULT_VALUE ON +DEFAULT_VALUE OFF VARIABLE_SCOPE GLOBAL VARIABLE_TYPE BOOLEAN -VARIABLE_COMMENT Reduce redo logging when natively creating indexes or rebuilding tables. Setting this OFF avoids delay due to page flushing and allows concurrent backup. +VARIABLE_COMMENT DEPRECATED. Ignored in MariaDB 10.5. Reduce redo logging when natively creating indexes or rebuilding tables. Enabling this may slow down backup and cause delay due to page flushing. NUMERIC_MIN_VALUE NULL NUMERIC_MAX_VALUE NULL NUMERIC_BLOCK_SIZE NULL |