MySQL 5.7 Release Notes
        
      There are two pairs of InnoDB
      INFORMATION_SCHEMA tables about compression
      that can provide insight into how well compression is working
      overall:
- INNODB_CMPand- INNODB_CMP_RESETprovide information about the number of compression operations and the amount of time spent performing compression.
- INNODB_CMPMEMand- INNODB_CMPMEM_RESETprovide information about the way memory is allocated for compression.