Percona Server is drop-in replacement for the popular MySQL, with full backward compatibility.
Percona Server provides diagnostic tools useful to DBAs, and more tunability of server behavior. Also included is Percona's online backup utility XtraBackup, the open source tool for the XtraDB / InnoDB.
Percona Server with XtraDB shows outstanding performance and scalability on today's high-end server systems with many CPUs and fast storage subsystems such as flash storage and SSD.
Here are some key features of "Percona Server":
· Scalability: Handles more concurrent transactions, and scales up on powerful servers.
· Performance: Fast IO path, improved internal cooperation, and fast checksums.
· Flexibility: Variable page size, better table and buffer pool management, and configurable insert buffer.
· Reliability: Resilience to corrupted data, and crash-safe transactional replication.
· Management: Online backup, InnoDB table import/export, fast recovery, and configurable data dictionary.
· Diagnostics: Improved profiling and instrumentation.
What's New in This Release: [ read full changelog ]
· In Ubuntu Precise libmysqlclient18 package was chosen from the distribution’s repository instead of Percona’s which could lead to package conflicts. Bug fixed #1174271.
· Fixed the RPM Percona-Server-shared-compat package naming issue that could lead to unresolved package dependencies when installing Percona Server 5.1. Bug fixed #893860.
· The log tracker thread was unaware of the situation when the oldest untracked log records are overwritten by the new log data. In some corner cases this could lead to assertion errors in the log parser or bad changed page data. Bug fixed #1108613.
· Percona Server wouldn’t start if the XtraDB changed page tracking was enabled and variable innodb_flush_method was set to ALL_O_DIRECT. Bug fixed #1131949.
· Fixed the RPM package dependencies for different major versions of Percona Server. Bug fixed #1167109.
· Fixed the CVE-2012-5627 vulnerability, where an unprivileged MySQL account owner could perform brute-force password guessing attack on other accounts efficiently. This bug fix comes originally from MariaDB (see MDEV-3915). Bug fixed #1172090.
· OpenSSL libraries were not found in 32-bit builds due to a typo. Bug fixed #1175447.
· Query to the INNODB_CHANGED_PAGES table would cause server to stop with an I/O error if a bitmap file in the middle of requested LSN range was missing. Bug fixed #1179974.
· Server would crash if an INNODB_CHANGED_PAGES query is issued that has an empty LSN range and thus does not need to read any bitmap files. Bug fixed #1184427.
· Incorrect schema definition for the User Statistics tables in INFORMATION_SCHEMA (CLIENT_STATISTICS, INDEX_STATISTICS, TABLE_STATISTICS, THREAD_STATISTICS, and USER_STATISTICS) led to the maximum counter values being limited to 32-bit signed integers. Fixed so that these values can be 64-bit unsigned integers now. Bug fixed #714925.
· mysql_set_permission was failing on Debian due to missing libdbd-mysql-perl package. Fixed by adding the package dependency. Bug fixed #1003776.
· XtraDB changed page tracking used to hold the log system mutex for the log reads needlessly, potentially limiting performance on write-intensive workloads. Bug fixed #1171699.
· Missing path separator between the directory and file name components in a bitmap file name could stop the server starting if the innodb_data_home_dir variable didn’t have the path separator at the end. Bug fixed #1181887.
· A warning is now returned if a bitmap file I/O error occurs after an INNODB_CHANGED_PAGES query started returning data to indicate an incomplete result set. Bug fixed #1185040.
· Fixed the upstream bug #69379 which caused MySQL clients to return bogus error number for host-not-found errors on Ubuntu 13.04. Bug fixed #1186690.
· Under very rare circumstances, deleting a zero-size bitmap file at the right moment would make server stop with an I/O error if changed page tracking is enabled. Bug fixed #1184517.
· The INNODB_CHANGED_PAGES table couldn’t be queried if the log tracker wasn’t running. Bug fixed #1185304.