Based on MySQL 5.5.29, including all the bug fixes in it, Percona Server 5.5.29-30.0 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 5.5.29-30.0 milestone at Launchpad.
Ported the Thread Pool patch from MariaDB. This feature enables the server to keep the top performance even with the increased number of client connections.
New user statements have been introduced for handling the XtraDB changed page tracking log files.
In addition to the --debug build option for build-binary.sh script, new --valgrind option has been introduced, which will build debug builds with the Valgrind instrumentation enabled.
The server could crash when executing an INSERT or UPDATE statement containing BLOB values for a compressed table. This regression was introduced in Percona Server 5.5.28-29.2. Bug fixed #1100159 (Laurynas Biveinis).
Percona Server would fail to install on a vanilla Ubuntu 12.04 server. Bug fixed #1103655 (Ignacio Nin).
The master thread was doing dirty buffer pool flush list reads to make its adaptive flushing decisions. Fixed by acquiring the flush list mutex around the list scans. Bug fixed #1083058 (Laurynas Biveinis).
Upstream changes made to improve InnoDB DROP TABLE performance were not adjusted for XtraDB. This could cause server assertion errors. Bugs fixed #934377, bug #1111211, bug #1116447 and #1110102 (Laurynas Biveinis).
The XtraDB used to print the open read view list without taking the kernel mutex. Thus any list element might become invalid during its iteration. Fixed by taking the kernel mutex. Bug fixed #1101030 (Laurynas Biveinis).
When option innodb_flush_method=O_DIRECT was set up, log bitmap files were created and treated as InnoDB data files for flushing purposes, which wasn’t original intention. Bug fixed #1105709 (Laurynas Biveinis).
INFORMATION_SCHEMA plugin name innodb_changed_pages serves also as a command line option, but it is also a prefix of another command line option innodb_changed_pages_limit. MySQL option handling would then shadow the former with the latter, resulting in start up errors. Fixed by renaming the innodb_changed_pages_limit option to innodb_max_changed_pages. Bug fixed #1105726 (Laurynas Biveinis).
Writing bitmap larger than 4GB would cause write to fail. Also a write error for every bitmap page, except the first one, would result in a heap corruption. Bug fixed #1111226 (Laurynas Biveinis).
Fixed the upstream bug #67504 that caused spurious duplicate key errors. Errors would happen if a trigger is fired while a slave was processing replication events for a table that is present only on slave server while there are updates on the replicated table on the master which is used in that trigger. For this to happen master needs to have more than one auto-increment table and the slave needs to have at least one of those tables specified in the replicate-ignore-table. Bug fixed #1068210 (George Ormond Lorch III).
Fixed failing rpm builds, that were caused by missing files. Bug fixed #1099809 (Alexey Bychko).
Fixed the upstream #68116 that caused the server crash with assertion error when InnoDB monitor with verbose lock info was used under heavy load. This bug is affecting only -debug builds. Bug fixed #1100178 (Laurynas Biveinis).
XtraDB changed page tracking wasn’t compatible with innodb_force_recovery=6. When starting the server log tracking initialization would fail. The server would abort on startup. Bug fixed #1083596 (Laurynas Biveinis).
Newly created bitmap file would silently overwrite the old one if they had the same file name. Bug fixed #1111144 (Laurynas Biveinis).
Optimizer_fix patch has been removed from Percona Server. Bug fixed #986247 (Stewart Smith).
InnoDB monitor was prefetching the data pages for printing lock information even if no lock information was going to be printed. Bug fixed #1100643 (Laurynas Biveinis).
InnoDB and the query plan information were being logged even if they weren’t enabled for the slow query log. Bug fixed #730173 (Laurynas Biveinis).
Other bug fixes: bug fixed #909376 (Laurynas Biveinis), bug fixed #1082437 (Laurynas Biveinis), bug fixed #1083669 (Laurynas Biveinis), bug fixed #1096904 (Laurynas Biveinis), bug fixed #1091712 (Laurynas Biveinis), bug fixed #1096899 (Laurynas Biveinis), bug fixed #1088954 (Laurynas Biveinis), bug fixed #1096895 (Laurynas Biveinis), bug fixed #1092142 (Laurynas Biveinis), bug fixed #1090874 (Laurynas Biveinis), bug fixed #1089961 (Laurynas Biveinis), bug fixed #1088867 (Laurynas Biveinis), bug fixed #1089031 (Laurynas Biveinis), bug fixed #1108874 (Laurynas Biveinis), bug fixed #1030783 (Laurynas Biveinis), and bug fixed #803072 (Laurynas Biveinis).