Based on MySQL 5.5.27, including all the bug fixes in it, Percona Server 5.5.27-29.0 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 5.5.27-29.0 milestone at Launchpad.
- Percona Server now supports XtraDB changed page tracking. This feature will be used for implementing faster incremental backups that use this information to avoid full data scans.
- Number of binlog files can be restricted when using Percona Server with the new max_binlog_files option.
- Fixed server assertion error related to buffer pool, only visible in debug builds. Bug fixed #905334 (Stewart Smith).
- Fix for bug #978036 introduced the innodb_sys_stats_root_page debugging option (only present in debug builds), rendering the previously-existing innodb_sys_stats option its prefix. As such, it became unsettable from command line. Fixed by renaming innodb_sys_stats_root_page to innodb_persistent_stats_root_page. Bug fixed #1013644 (Laurynas Biveinis).
- Multiple adaptive hash index partitions would cause overly large hash index. Fixed by changing the way partition sizes are calculated initially. Bug fixed #1018264 (George Ormond Lorch III).
- Postfix would crash on CentOS/RHEL 6.x when using shared dependency (libmysqlclient.so). Fixed by building packages with OpenSSL support rather than the bundled YaSSL library. Bug fixed #1028240 (Ignacio Nin).
- Fixed the issue where LRU dump would hold LRU_list_mutex during the entire dump process. Now the mutex is periodically released in order not to block server while the dump is in progress. Bug fixed #686534 (George Ormond Lorch III).
- Option expire_logs_days was broken by group_commit patch introduced in Percona Server 5.5.18-23.0. Bug fixed #1006214 (Stewart Smith).
- Fixed issue where innodb_blocking_lru_restore did not take an optional bool argument similar to other bool options. Bug fixed #881001 (George Ormond Lorch III).
- The binlog shouldn’t be rotated while it contains XA transactions in the PREPARED state. Bug fixed #1036040 (Stewart Smith).
- Flashcache support resulted in confusing messages in the error log on Percona Server startup even when flashcache was not used. This was fixed by adding new boolean option –flashcache. When set to 0 (default), flashcache checks are disabled and when set to 1 checks are enabled. Error message has been made more verbose, it now includes the error number and system error message as well. Bug fixed #747032 (Sergei Glushchenko).
- Custom server builds would crash when compiled with a non-default maximum number of indexes per table. Upstream MySQL bugs: #54127, #61178, #61179 and #61180. Bug fixed #1042517 (Sergei Glushchenko).
Release notes for Percona Server 5.5.27-29.0 are available in our online documentation.