MySQL 5.7 Release Notes
The INNODB_CMP and
INNODB_CMP_RESET tables provide
status information about operations related to compressed
tables, which are described in
Section 14.9, “InnoDB Table and Page 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
cumulative statistics since InnoDB was started.
For the table definition, see Section 24.4.5, “The INFORMATION_SCHEMA INNODB_CMP and INNODB_CMP_RESET Tables”.