MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6

24.32.15 The INFORMATION_SCHEMA INNODB_METRICS Table

The INNODB_METRICS table provides a wide variety of InnoDB performance information, complementing the specific focus areas of the Performance Schema tables for InnoDB. With simple queries, you can check the overall health of the system. With more detailed queries, you can diagnose issues such as performance bottlenecks, resource shortages, and application issues.

Each monitor represents a point within the InnoDB source code that is instrumented to gather counter information. Each counter can be started, stopped, and reset. You can also perform these actions for a group of counters using their common module name.

By default, relatively little data is collected. To start, stop, and reset counters, set one of the system variables innodb_monitor_enable, innodb_monitor_disable, innodb_monitor_reset, or innodb_monitor_reset_all, using the name of the counter, the name of the module, a wildcard match for such a name using the % character, or the special keyword all.

For usage information, see Section 14.16.6, “InnoDB INFORMATION_SCHEMA Metrics Table”.

The INNODB_METRICS table has these columns:

Example

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME='dml_inserts'\G
*************************** 1. row ***************************
           NAME: dml_inserts
      SUBSYSTEM: dml
          COUNT: 3
      MAX_COUNT: 3
      MIN_COUNT: NULL
      AVG_COUNT: 0.046153846153846156
    COUNT_RESET: 3
MAX_COUNT_RESET: 3
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULL
   TIME_ENABLED: 2014-12-04 14:18:28
  TIME_DISABLED: NULL
   TIME_ELAPSED: 65
     TIME_RESET: NULL
         STATUS: enabled
           TYPE: status_counter
        COMMENT: Number of rows inserted

Notes