Options that make XtraDB tablespaces not compatible with MySQL Options that make XtraDB tablespaces not compatible with MySQL¶
Fast checksums¶
Enabling innodb_fast_checksum will use more CPU-efficient algorithm, based on 4-byte words which can be beneficial for some workloads. Once enabled, turning it off will require table to be dump/imported again, since Percona Server will fail to start on data files created when innodb_fast_checksums was enabled.
In case you’ve migrated from Percona Server to MySQL you could get the “corrupted checksum” error message. In order to recover that table you’ll need to:
- Reinstall Percona Server to read your tables that were created with fast checksums.
- Dump the tables (or temporarily convert them to MyISAM).
- Install stock MySQL (or at least disable fast checksums).
- Restore the InnoDB tables (or convert back from MyISAM).
Note
This feature has been deprecated after Percona Server 5.5.28-29.2 and it is not available in Percona Server 5.6, because the innodb_checksum_algorithm feature in MySQL 5.6 makes it redundant.
Page sizes other than 16KiB¶
This is controlled by variable innodb_page_size. Changing the page size for an existing database is not supported. Table will need to be dumped/imported again if compatibility with MySQL is required.
Note
This feature has been deprecated in the Percona Server 5.5.30-30.2. It has been replaced by the upstream version released in MySQL 5.6.4.
Relocation of the doublewrite buffer¶
Variable innodb_doublewrite_file provides an option to put the buffer on a dedicated disk in order to parallelize I/O activity on the buffer and on the tablespace. Only in case of crash recovery this variable cannot be changed, in all other cases it can be turned on/off without breaking the compatibility.
Note
This feature has not been ported to Percona Server 5.6.
