Based on MySQL 5.5.21, including all the bug fixes in it, Percona Server 5.5.21-25.1 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release can be found in the 5.5.21-25.1 milestone at Launchpad.
We are doing another release based on MySQL 5.5.21 as we have a couple of important bug fixes that we wish to make available.
- Fixed a memory corruption regression introduced in 5.5.18-23.0. Bug fixed #915814 (Alexey Kopytov).
- Fixed InnoDB compilation warnings on CentOS 5. Bug fixed #962940 (Laurynas Biveinis).
- Fixed MySQL upstream bug #64160 that was causing issues on upgrade to 5.5.20 and 5.5.21. Bug fixed #966844 (Stewart Smith).
Full release notes are available in the documentation.