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2022-12-15 MySQL

Monitoring Performance

Global Status#

SHOW GLOBAL STATUS;

Performance Schema#

SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
   WHERE TABLE_SCHEMA = 'performance_schema';

Query Stats#

Closest to Pg Stat Statments

SELECT *
   FROM performance_schema.events_statements_summary_by_digest
   ORDER BY avg_timer_wait DESC
   LIMIT 20

Sys Schema#

SELECT * FROM sys.statement_analysis;

SELECT * FROM sys.statements_with_runtimes_in_95th_percentile;

Looks like time is measured in picoseconds. 1000 pico seconds is a nanosecond. 1000 nanoseconds is a microsecond, 1000 microseconds is a millisecond, 1000 milliseconds is a second.

Sections:

Reset Stats#

CALL sys.ps_truncate_all_tables(FALSE);

Mysql: How to flush performance_schema stats without restarting MySQL?

Sources#