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https://dev.mysql.com/doc/refman/8.0/en/select-optimization.html
With efficient use of the InnoDB buffer pool, MyISAM key cache, and the MySQL query cache, repeated queries run faster because the results are retrieved from memory the second and subsequent times. Tuning these statements is a top priority, whether ... Queries, in the form of SELECT statements, perform all the lookup operations in the ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-statistics-estimation.html
To improve the start up time of the mysql client and to updating statistics, you can turn off auto-rehash using the --disable-auto-rehash option. Starting a mysql client with the --auto-rehash option enabled, which is the default. InnoDB detects ...
https://dev.mysql.com/doc/refman/8.0/en/optimizing-queries-myisam.html
Some general tips for speeding up queries on MyISAM tables: To help MySQL better optimize queries, use ANALYZE TABLE or run myisamchk --analyze on a table after it has been loaded with data. (For unique indexes, this is always 1.) MySQL uses this ...This updates a value for each index part that indicates the average number of rows that have the same ...
https://dev.mysql.com/doc/refman/8.0/en/partitioning-hash.html
This can simply be the name of a column whose type is one of MySQL's integer types. You should also keep in mind that this expression is evaluated each time a row is inserted or updated (or possibly deleted); this means that very complex expressions ... Partitioning by HASH is used primarily to ensure an even distribution of data among a predetermined number of ...
https://dev.mysql.com/doc/refman/8.0/en/table-locking.html
MySQL uses table locking (instead of page, row, or column locking) for all storage engines except InnoDB. But because only one session can write to a table at any one time, for best performance with these other storage engines, use them primarily ...
https://dev.mysql.com/doc/refman/8.0/en/information-schema-innodb-tablestats-table.html
This data is used by the MySQL optimizer to calculate which index to use when querying an InnoDB table. Statistics are collected again the next time the table is accessed. This column is reset each time table statistics are recalculated AUTOINC The ... The INNODB_TABLESTATS table provides a view of low-level status information about InnoDB ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-compression-tuning-monitoring.html
To dig deeper into performance considerations for compressed tables, you can monitor compression performance at runtime using the Information Schema tables described in Example 17.1, “Using the Compression Information Schema Tables”. This ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-performance-spin_lock_polling.html
They can be specified in a MySQL option file or modified at runtime using a SET GLOBAL statement. On a multi-core system, it can be more efficient for a thread to continuously check if it can acquire a mutex or rw-lock for a period of time before it ... InnoDB mutexes and rw-locks are typically reserved for short ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-replication-applier-status-by-worker-table.html
Before MySQL 8.0.13, this timestamp was refreshed when a transaction was retried due to a transient error, so it showed the timestamp for the most recent attempt to apply the transaction. The applier threads on a multithreaded replica are sometimes ... This table provides details of the transactions handled by applier threads on a replica or Group Replication group ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-startup-configuration.html
To use the MySQL Performance Schema, it must be enabled at server startup to enable event collection to occur. For example, use these lines in the server my.cnf file: [mysqld] performance_schema=ON If the server is unable to allocate any internal ...To enable or disable it explicitly, start the server with the performance_schema variable set to an appropriate ...