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21.9.9.2. The performance_timers Table

The performance_timers table shows which event timers are available:

mysql> SELECT * FROM
        performance_timers;+-------------+-----------------+------------------+----------------+| TIMER_NAME  | TIMER_FREQUENCY | TIMER_RESOLUTION | TIMER_OVERHEAD |+-------------+-----------------+------------------+----------------+| CYCLE       |      2389029850 |                1 |             72 || NANOSECOND  |            NULL |             NULL |           NULL || MICROSECOND |         1000000 |                1 |            585 || MILLISECOND |            1035 |                1 |            738 || TICK        |             101 |                1 |            630 |+-------------+-----------------+------------------+----------------+

If the values associated with a given timer name are NULL, that timer is not supported on your platform. The rows that do not contain NULL indicate which timers you can use in setup_timers.

The performance_timers table has these columns: