Upgrading to MySQL 5.1
Jul 01, 2010
We spent a lot of time to confirm that MySQL 5.1 was stable and performant using benchmarks and our production workload. mk-upgrade from Maatkit was one of the tools we used. Concurrent dump/reload tests were done to measure performance and check for data drift after reload. A custom tool that replays production workload was run to compare performance between MySQL 5.0 and 5.1. We started with MySQL 5.1.38 and now are at MySQL 5.1.47 with several backports for bugs that will be fixed in more recent 5.1 releases or in 5.5.
We found a few serious bugs in MySQL 5.1 during this process. We fixed some of the bugs, worked with MySQL support to debug some of them and waited for MySQL to fix many others. MySQL support and developers were a huge help. It is great to have so much access to experts. MySQL has been getting things done at an amazing rate this year.
I am excited about MySQL 5.1 and 5.5. With a few recent changes to the Facebook patch we have been able to increase peak QPS by more than 2X and peak IOPs by more than 3X using benchmarks. There are more improvements to be done. Whether or not we match the benchmark results in production, I much prefer an RDBMS that can exceed 100,000 QPS and IOPs than one that is saturated at 10,000. Any of the changes we make for 5.1 will look even better with MySQL 5.5 given support for multiple InnoDB buffer pool instances and some of the changes above the storage engine layer that aren’t easy to describe in a few sentences.
