Performance Schema events_stages_history_long Table

MariaDB starting with 10.0

The events_stages_history_long table, along with many other new Performance Schema tables, was added in MariaDB 10.0

The events_stages_history_long table by default contains the ten thousand most recent completed stage events. This number can be adjusted by setting the performance_schema_events_stages_history_long_size system variable when the server starts up.

The table structure is identical to the events_stage_current table structure, and contains the following columns:

ColumnDescription
THREAD_IDThread associated with the event. Together with EVENT_ID uniquely identifies the row.
EVENT_IDThread's current event number at the start of the event. Together with THREAD_ID uniquely identifies the row.
END_EVENT_IDNULL when the event starts, set to the thread's current event number at the end of the event.
EVENT_NAMEEvent instrument name and a NAME from the setup_instruments table
SOURCEName and line number of the source file containing the instrumented code that produced the event.
TIMER_STARTValue in picoseconds when the event timing started or NULL if timing is not collected.
TIMER_ENDValue in picoseconds when the event timing ended, or NULL if timing is not collected.
TIMER_WAITValue in picoseconds of the event's duration or NULL if timing is not collected.
NESTING_EVENT_IDEVENT_ID of event within which this event nests.
NESTING_EVENT_TYPENesting event type. Either statement, stage or wait.

It is possible to empty this table with a TRUNCATE TABLE statement.

events_stages_current and events_stages_history are related tables.

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