TheINNODB_CMPandINNODB_CMP_RESETtables provide status information about operations related to compressed tables, which are described inSection 15.9, “InnoDB Table and Page Compression”. ThePAGE_SIZEcolumn reports the compressedpage size.

These two tables have identical contents, but reading fromINNODB_CMP_RESETresets the statistics on compression and uncompression operations. For example, if you archive the output ofINNODB_CMP_RESETevery 60 minutes, you see the statistics for each hourly period. If you monitor the output ofINNODB_CMP(making sure never to readINNODB_CMP_RESET), you see the cumulative statistics since InnoDB was started.

For the table definition, seeSection 26.4.6, “The INFORMATION_SCHEMA INNODB_CMP and INNODB_CMP_RESET Tables”.