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29.12.4.3 The events_waits_history_long Table

The events_waits_history_long table contains N the most recent wait events that have ended globally, across all threads. Wait events are not added to the table until they have ended. When the table becomes full, the oldest row is discarded when a new row is added, regardless of which thread generated either row.

The Performance Schema autosizes the value of N during server startup. To set the table size explicitly, set the performance_schema_events_waits_history_long_size system variable at server startup.

The events_waits_history_long table has the same columns as events_waits_current. See Section 29.12.4.1, “The events_waits_current Table”. Unlike events_waits_current, events_waits_history_long has no indexing.

TRUNCATE TABLE is permitted for the events_waits_history_long table. It removes the rows.

For more information about the relationship between the three wait event tables, see Section 29.9, “Performance Schema Tables for Current and Historical Events”.

For information about configuring whether to collect wait events, see Section 29.12.4, “Performance Schema Wait Event Tables”.