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https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam.html
The MyISAM storage engine performs best with read-mostly data or with low-concurrency operations, because table locks limit the ability to perform simultaneous updates. In MySQL, InnoDB is the default storage engine rather than MyISAM.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-events-statements-current-table.html
The table stores one row per thread showing the current status of the thread's most recent monitored statement event, so there is no system variable for configuring the table size. Of the tables that contain statement event rows, ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instance-tables.html
They provide event names and explanatory notes or status information: cond_instances: Condition synchronization object instances file_instances: File instances mutex_instances: Mutex synchronization object instances rwlock_instances: Lock ...Each ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-log-status-table.html
The log_status table provides information that enables an online backup tool to copy the required log files without locking those resources for the duration of the copy process. When the log_status table is queried, the server blocks logging and ...
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-statement-digests.html
For example, table columns that show wait times, lock times, or index use may highlight types of queries that are inefficient. The MySQL server is capable of maintaining statement digest information. The digesting process converts each SQL ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-transaction-tables.html
Transactions explicitly end with these statements: COMMIT | ROLLBACK | XA COMMIT | XA ROLLBACK Transactions also end implicitly, by execution of DDL statements, locking statements, and server administration statements. Within the event hierarchy, ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-wait-summary-tables.html
row *************************** EVENT_NAME: wait/synch/mutex/sql/BINARY_LOG::LOCK_index COUNT_STAR: 8 SUM_TIMER_WAIT: 2119302 MIN_TIMER_WAIT: 196092 AVG_TIMER_WAIT: 264912 MAX_TIMER_WAIT: 569421 ... row *************************** EVENT_NAME: ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema.html
Event collection provides access to information about synchronization calls (such as for mutexes) file and table I/O, table locks, and so forth for the server and for several storage engines. The MySQL Performance Schema is a feature for monitoring ...
https://dev.mysql.com/doc/refman/8.4/en/query-log.html
This logging order is in contrast with that of the binary log, for which statements are written after they are executed but before any locks are released. The general query log is a general record of what mysqld is doing. The server writes ...