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Determining What Is Instrumented

It is always possible to determine what instruments the Performance Schema includes by checking

the setup_instruments table. For example, to see what file-related events are instrumented for the

InnoDB storage engine, use this query:

mysql>SELECT * FROM setup_instruments WHERE NAME LIKE 'wait/io/file/innodb/%';

NAME | ENABLED | TIMED |	-+-----	----+--------
wait/io/file/innodb/innodb data file	| YES	| YES |
wait/io/file/innodb/innodb log file |	I YES |	YES |
wait/io/file/innodb/innodb temp file	| YES	| YES |
	.+-----	----+--------

An exhaustive description of precisely what is instrumented is not given in this documentation, for several reasons:

•    What is instrumented is the server codę. Changes to this codę occur often, which also affects the set

of instruments.

•    It is not practical to list all the instruments because there are hundreds of them.

•    As described earlier, it is possible to find out by querying the setup_instruments table. This

information is always up to datę for your version of MySQL, also includes instrumentation for

instrumented plugins you might have installed that are not part of the core server, and can be used by automated tools.