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https://dev.mysql.com/doc/refman/8.4/en/performance-schema-memory-model.html
The buffers are global to the server, so the instruments are displayed only in the memory_summary_global_by_event_name table, and not in other memory_summary_by_xxx_by_event_name tables. Memory used depends on the load actually seen, not the load ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-memory-summary-tables.html
Operation counts help to understand or tune the overall pressure the server is putting on the memory allocator, which has an impact on performance. It has these effects: In general, truncation resets the baseline for statistics, but does not change ...Allocating a single byte one million times is not the same as allocating one million bytes a single time; tracking both sizes and counts can expose the ...
https://dev.mysql.com/doc/refman/8.4/en/repair-table.html
If the server exits during a REPAIR TABLE operation, it is essential after restarting it that you immediately execute another REPAIR TABLE statement for the table before performing any other operations on it. REPAIR TABLE Options NO_WRITE_TO_BINLOG ...[QUICK] [EXTENDED] [USE_FRM] REPAIR TABLE repairs a possibly corrupted table, for certain storage engines ...
https://dev.mysql.com/doc/refman/8.4/en/replication-binlog-encryption-scope.html
Existing binary log files and relay log files that were present on the server when you started encryption are not encrypted. When binary log encryption is active on the server, temporary files used to hold the binary log cache are encrypted using ...
https://dev.mysql.com/doc/refman/8.4/en/replication-channels.html
In MySQL multi-source replication, a replica opens multiple replication channels, one for each source server. The maximum number of channels that can be created on one replica server in a multi-source replication topology is 256. This is because ...
https://dev.mysql.com/doc/refman/8.4/en/replication-delayed.html
MySQL supports delayed replication such that a replica server deliberately executes transactions later than the source by at least a specified amount of time. This section describes delayed replication between servers which are all using these ...
https://dev.mysql.com/doc/refman/8.4/en/replication-implementation.html
Replication is based on the source server keeping track of all changes to its databases (updates, deletes, and so on) in its binary log. The binary log serves as a written record of all events that modify database structure or content (data) from ...Typically, SELECT statements are not recorded because they modify neither database structure nor ...
https://dev.mysql.com/doc/refman/8.4/en/replication-mode-change-online-concepts.html
Before setting the replication mode of an online server, it is important to understand some key concepts of replication. This section explains these concepts and is essential reading before attempting to modify the replication mode of an online ...
https://dev.mysql.com/doc/refman/8.4/en/replication-privilege-checks-recover.html
If a privilege check against the PRIVILEGE_CHECKS_USER account fails, the transaction is not executed and replication stops for the channel. Details of the error and the last applied transaction are recorded in the Performance Schema ...
https://dev.mysql.com/doc/refman/8.4/en/replication-semisync-interface.html
To check the current values of the status variables for semisynchronous replication, use SHOW VARIABLES: mysql> SHOW VARIABLES LIKE 'rpl_semi_sync%'; All the rpl_semi_sync_xxx system variables are described at Section 19.1.6.2, “Replication Source ... When you install the source and replica plugins for semisynchronous replication (see Section 19.4.10.1, “Installing Semisynchronous Replication”), system variables become available to control plugin ...