Performance Schema Table Descriptions
Tables in the performance_schema database can be grouped as follows:
• Setup tables. These tables are used to configure and display monitoring characteristics.
• Current events table. The events_waits_current table contains the most recent event for each
• History tables. These tables have the same structure as events_waits_current but contain
more rows. The events_waits_history table contains the most recent 10 events per thread.
events_waits_history_long contains the most recent 10,000 events.
To change the sizes of these tables, set the
performance_schema_events_waits_history_size  and
performance_schema_events_waits_history_long_size  system variables at server
• Summary tables. These tables contain information aggregated over groups of events, including those
that have been discarded from the history tables.
• Instance tables. These tables document what types of objects are instrumented. An instrumented
object, when used by the server, produces an event. These tables provide event names and
explanatory notes or status information.
• Miscellaneous tables. These do not fall into any of the other table groups.
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