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29.12.20.6 对象等待汇总表

性能模式维护了objects_summary_global_by_type表来聚合对象等待事件。

示例对象等待事件汇总信息:

mysql> SELECT * FROM performance_schema.objects_summary_global_by_type\G
...
*************************** 3. row ***************************
   OBJECT_TYPE: TABLE
 OBJECT_SCHEMA: test
   OBJECT_NAME: t
    COUNT_STAR: 3
SUM_TIMER_WAIT: 263126976
MIN_TIMER_WAIT: 1522272
AVG_TIMER_WAIT: 87708678
MAX_TIMER_WAIT: 258428280
...
*************************** 10. row ***************************
   OBJECT_TYPE: TABLE
 OBJECT_SCHEMA: mysql
   OBJECT_NAME: user
    COUNT_STAR: 14
SUM_TIMER_WAIT: 365567592
MIN_TIMER_WAIT: 1141704
AVG_TIMER_WAIT: 26111769
MAX_TIMER_WAIT: 334783032
...

对象objects_summary_global_by_type表具有以下分组列来指示如何聚合事件:OBJECT_TYPEOBJECT_SCHEMAOBJECT_NAME。每一行总结了给定对象的事件。

objects_summary_global_by_type具有与events_waits_summary_by_xxx表相同的摘要列。请参阅第29.12.20.1节,“等待事件汇总表”

对象objects_summary_global_by_type具有这些索引:

  • 主键在(OBJECT_TYPEOBJECT_SCHEMAOBJECT_NAME)上

TRUNCATE TABLE允许对对象汇总表进行。它将摘要列重置为零,而不是删除行。