MySQL 5.5 Release Notes
The INNODB_CMP and
INNODB_CMP_RESET
tables contain status information about operations related to
compressed tables, which are described in
Section 14.12, “InnoDB Table Compression”. The
PAGE_SIZE column reports the compressed
page size.
These two tables have identical contents, but reading from
INNODB_CMP_RESET
resets the statistics on compression and uncompression
operations. For example, if you archive the output of
INNODB_CMP_RESET
every 60 minutes, you see the statistics for each hourly period.
If you monitor the output of
INNODB_CMP (making sure never to
read
INNODB_CMP_RESET),
you see the cumulated statistics since InnoDB
was started.
For the table definition, see Section 21.28.4, “The INFORMATION_SCHEMA INNODB_CMP and INNODB_CMP_RESET Tables”.