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https://dev.mysql.com/doc/refman/8.4/en/performance-schema-examples.html
To begin, you should have a repeatable use case where performance is deemed “too slow” and needs optimization, and you should enable all instrumentation (no pre-filtering at all). The Performance Schema is a tool to help a DBA do performance ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrument-naming.html
An instrument name consists of a sequence of elements separated by '/' characters. Example names: wait/io/file/myisam/log wait/io/file/mysys/charset wait/lock/table/sql/handler wait/synch/cond/mysys/COND_alarm ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-query-profiling.html
The following example demonstrates how to use Performance Schema statement events and stage events to retrieve data comparable to profiling information provided by SHOW PROFILES and SHOW PROFILE statements. The setup_actors table can be used to ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-rwlock-instances-table.html
Shared-exclusive access is otherwise known as an sxlock and optimizes concurrency and improves scalability for read-write workloads. The rwlock_instances table lists all the rwlock (read write lock) instances seen by the Performance Schema while ...
https://dev.mysql.com/doc/refman/8.4/en/problems-with-float.html
Floating-point numbers sometimes cause confusion because they are approximate and not stored as exact values. A floating-point value as written in an SQL statement may not be the same as the value represented internally. Attempts to treat ...
https://dev.mysql.com/doc/refman/8.4/en/repair-table.html
[QUICK] [EXTENDED] [USE_FRM] REPAIR TABLE repairs a possibly corrupted table, for certain storage engines only. Although normally you should never have to run REPAIR TABLE, if disaster strikes, this statement is very likely to get back all your data ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-flush.html
The FLUSH TABLES, ANALYZE TABLE, OPTIMIZE TABLE, and REPAIR TABLE statements are written to the binary log and thus replicated to replicas. Some forms of the FLUSH statement are not logged because they could cause problems if replicated to a ...
https://dev.mysql.com/doc/refman/8.4/en/replication-options-binary-log.html
Typically, the benefits of setting a delay outweigh the drawbacks, but tuning should always be carried out to determine the optimal setting. Startup Options Used with Binary Logging System Variables Used with Binary Logging You can use the mysqld ...
https://dev.mysql.com/doc/refman/8.4/en/replication-solutions-backups-read-only.html
Note The instructions in this section place the server to be backed up in a state that is safe for backup methods that get the data from the server, such as mysqldump (see Section 6.5.4, “mysqldump — A Database Backup Program”). You should not ...
https://dev.mysql.com/doc/refman/8.4/en/select-benchmarking.html
The built-in MySQL functions are typically highly optimized, but there may be some exceptions. To measure the speed of a specific MySQL expression or function, invoke the BENCHMARK() function using the mysql client program. The return value is ...