MySQL 8.0 Reference Manual Including MySQL NDB Cluster 8.0

26.12.18.4 The performance_timers Table

The performance_timers table shows which event timers are available:

mysql> SELECT * FROM performance_schema.performance_timers;
+-------------+-----------------+------------------+----------------+
| TIMER_NAME  | TIMER_FREQUENCY | TIMER_RESOLUTION | TIMER_OVERHEAD |
+-------------+-----------------+------------------+----------------+
| CYCLE       |      2389029850 |                1 |             72 |
| NANOSECOND  |      1000000000 |                1 |            112 |
| MICROSECOND |         1000000 |                1 |            136 |
| MILLISECOND |            1036 |                1 |            168 |
+-------------+-----------------+------------------+----------------+

If the values associated with a given timer name are NULL, that timer is not supported on your platform. For an explanation of how event timing occurs, see Section 26.4.1, “Performance Schema Event Timing”.

The performance_timers table has these columns:

The performance_timers table has these indexes:

TRUNCATE TABLE is not permitted for the performance_timers table.