Oracle, the parent company of MySQL through their Sun Microsystems purchase, has announced the release-ready update for MySQL 5.5. This release promises performance gains of up to 360% for read/write on Linux platforms and over 600% on Windows Servers. Read on for a list of the new MySQL features for both Windows and Linux in the GA release.
When MySQL was purchased from being a Sun Micro, open-source product, there were a lot of fears that MySQL release cycles would be stopped by Oracle. On December 15th, Oracle announced their first major release for MySQL: 5.5.
MySQL 5.5 was built heavily by the user community feedback on the release candidate and offers significant improvements in scalability and performance. Prior to this release, 5.4 was the last update released by Sun back in April, 2009. Suffice to say, this MySQL update release was long-overdue.
So, you're probably wondering what's in this release that's so special? Let's break that down for you and you can start planning which features are going to benefit you the most.
Unix/Linux Performance It seems that a lot of the features of MySQL 5.5 are around InnoDB performance. In fact, InnoDB is now the default engine in MySQL 5.5's GA release. What this means is that from the initial install and without configuration, foreign key constraints and transaction-level sql are now available.
MySQL did this because now, with performance enhancements including those from Percona, they InnoDB implementation now has a 300%+ improvement in read/writes. With this, the read/write locks that would happen at the lower levels in the mutex are now gone. This is, in part, because the connection pool limit of 1024 is also now gone.
Also offered in this GA release, MySQL has added in what is called a performance_schema. By using this, you are able to drill down into the metrics of how queries are being executed and monitors every server interaction and event. Not necessarily something to leave live in production for a day, but turning this on can give you valuable performance and scale information to improve your systems.
Hooray for performance! Almost worth the year's wait.
A Quick Plug for Percona
We've worked with some of the folks at Percona closely in the past. We use their builds, they are really smart folks...and they really understand the payoffs of micro-optimizations on high-traffic DBs. Their software is 100% free...download Percona builds for MySQL and run some tests for yourself.
Chances are you have a mixed environment. Using MySQL 5.5 you cannow rely better on your replication including linux to linux and linuxto Windows replication. Replication machines now provide what is calleda heartbeat to signal the master db that it is alive and online, andvice versa. The result is reliable replication.
MySQL also introduced some enhancements to circular replication. In cases where you have a multi-master setup, if you remove a master from an old version of MySQL, replication would fail. This version introduces what looks like the DB equivalent of RAID hot-swapping of the Master, where replication doesn't fail but gracefully falls over.
Semi-Synchronous Replication is another feature of MySQL's better replication. In this, rather than try to poll and make sure all slaves are caught up and replicated by the Master, the slaves themselves can interact and receive data updates from other slaves. This is all normal, but now with MySQL 5.5 the replication can take a time-out without raising flags and also gracefully catch itself up from another slave in the command chain.