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MySQL Performance Schema  /  Performance Schema Table Descriptions  /  Performance Schema Summary Tables

10.9 Performance Schema Summary Tables

Summary tables provide aggregated information for terminated events over time. The tables in this group summarize event data in different ways.

Each summary table has grouping columns that determine how to group the data to be aggregated, and summary columns that contain the aggregated values. Tables that summarize events in similar ways often have similar sets of summary columns and differ only in the grouping columns used to determine how events are aggregated.

Summary tables can be truncated with TRUNCATE TABLE. Generally, the effect is to reset the summary columns to 0 or NULL, not to remove rows. This enables you to clear collected values and restart aggregation. That might be useful, for example, after you have made a runtime configuration change. Exceptions to this truncation behavior are noted in individual summary table sections.

Wait Event Summaries

Table 10.3 Performance Schema Wait Event Summary Tables

Table Name Description
events_waits_summary_by_account_by_event_name Wait events per account and event name
events_waits_summary_by_host_by_event_name Wait events per host name and event name
events_waits_summary_by_instance Wait events per instance
events_waits_summary_by_thread_by_event_name Wait events per thread and event name
events_waits_summary_by_user_by_event_name Wait events per user name and event name
events_waits_summary_global_by_event_name Wait events per event name

Stage Summaries

Table 10.4 Performance Schema Stage Event Summary Tables

Table Name Description
events_stages_summary_by_account_by_event_name Stage events per account and event name
events_stages_summary_by_host_by_event_name Stage events per host name and event name
events_stages_summary_by_thread_by_event_name Stage waits per thread and event name
events_stages_summary_by_user_by_event_name Stage events per user name and event name
events_stages_summary_global_by_event_name Stage waits per event name

Statement Summaries

Table 10.5 Performance Schema Statement Event Summary Tables

Table Name Description
events_statements_summary_by_account_by_event_name Statement events per account and event name
events_statements_summary_by_digest Statement events per schema and digest value
events_statements_summary_by_host_by_event_name Statement events per host name and event name
events_statements_summary_by_thread_by_event_name Statement events per thread and event name
events_statements_summary_by_user_by_event_name Statement events per user name and event name
events_statements_summary_global_by_event_name Statement events per event name

Object Wait Summaries

Table 10.6 Performance Schema Object Event Summary Tables

Table Name Description
objects_summary_global_by_type Object summaries

File I/O Summaries

Table 10.7 Performance Schema File I/O Event Summary Tables

Table Name Description
file_summary_by_event_name File events per event name
file_summary_by_instance File events per file instance

Table I/O and Lock Wait Summaries

Table 10.8 Performance Schema Table I/O and Lock Wait Event Summary Tables

Table Name Description
table_io_waits_summary_by_index_usage Table I/O waits per index
table_io_waits_summary_by_table Table I/O waits per table
table_lock_waits_summary_by_table Table lock waits per table

Socket Summaries

Table 10.9 Performance Schema Socket Event Summary Tables

Table Name Description
socket_summary_by_event_name Socket waits and I/O per event name
socket_summary_by_instance Socket waits and I/O per instance