binlog_space_limit is a variable in Percona server used to limit the total size of all binary logs. This implementation is based on code from Percona server 5.7. In MariaDB we decided to call the variable max-binlog-total-size to be similar to max-binlog-size. This makes it easier to find in the output from 'mariadbd --help --verbose'). MariaDB will also support binlog_space_limit for compatibility with Percona. Some internal notes to explain implementation notes: - When running MariaDB does not delete binary logs that are either used by slaves or have active xid that are not yet committed. Some implementation notes: - max-binlog-total-size is by default 0 (no limit). - max-binlog-total-size can be changed without server restart. - Binlog file sizes are checked on startup, or if max-binlog-total-size is set to a value > 0, not for every log write. The total size of all binary logs is cached and dynamically updated when updating the binary log on binary log rotation. - max-binlog-total-size is checked against existing log files during serverstart, binlog rotation, FLUSH LOGS, when writing to binary log or when max-binlog-total-size changes value. - Option --slave-connections-needed-for-purge with 1 as default added. This allows one to ensure that we do not delete binary logs if there is less than 'slave-connections-needed-for-purge' connected. Without this option max-binlog-total-size would potentially delete binlogs needed by slaves on server startup or when a slave disconnects as there are then no connected slaves to protect active binlogs. - PURGE BINARY LOGS TO ... will be executed as if slave-connectitons-needed-for-purge would be zero. In other words it will do the purge even if there is no slaves connected. If there are connected slaves working on the logs, these will be protected. - If binary log is on and max-binlog-total_size <> 0 then the status variable 'Binlog_disk_use' shows the current size of all old binary logs + the state of the current one. - Removed test of strcmp(log_file_name, log_info.log_file_name) in purge_logs_before_date() as this is tested in can_purge_logs() - To avoid expensive calls of log_in_use() we cache the result for the last log that is in use by a slave. Future calls to can_purge_logs() for this binary log will be quickly detected and false will be returned until a slave starts working on a new log. - Note that after a binary log rotation caused by max_binlog_size, the last log will not be purged directly as it is still in use internally. The next binary log write will purge binlogs if needed. Reviewer:Kristian Nielsen <knielsen@knielsen-hq.org>
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MariaDB: The open source relational database
MariaDB was designed as a drop-in replacement of MySQL(R) with more features, new storage engines, fewer bugs, and better performance.
MariaDB is brought to you by the MariaDB Foundation and the MariaDB Corporation. Please read the CREDITS file for details about the MariaDB Foundation, and who is developing MariaDB.
MariaDB is developed by many of the original developers of MySQL who now work for the MariaDB Corporation, the MariaDB Foundation and by many people in the community.
MySQL, which is the base of MariaDB, is a product and trademark of Oracle Corporation, Inc. For a list of developers and other contributors, see the Credits appendix. You can also run 'SHOW authors' to get a list of active contributors.
A description of the MariaDB project and a manual can be found at:
https://mariadb.com/kb/en/mariadb-vs-mysql-features/
https://mariadb.com/kb/en/mariadb-versus-mysql-compatibility/
https://mariadb.com/kb/en/new-and-old-releases/
Help
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Licensing
NOTE:
MariaDB is specifically available only under version 2 of the GNU General Public License (GPLv2). (I.e. Without the "any later version" clause.) This is inherited from MySQL. Please see the README file in the MySQL distribution for more information.
License information can be found in the COPYING file. Third party license information can be found in the THIRDPARTY file.
Bug Reports
Bug and/or error reports regarding MariaDB should be submitted at: https://jira.mariadb.org
For reporting security vulnerabilities, see our security-policy.
The code for MariaDB, including all revision history, can be found at: https://github.com/MariaDB/server