I recently worked on upgrading MySQL from one of very early MySQL 5.0 versions to Percona Server 5.1. This was a classical upgrade scenario which can cause surprises. Master and few slaves need to be upgraded. It is a shared database used by tons of applications written by many people over more than 5 years [...]
Percona Server security fix releases
As you may know MySQL ® announced 5.0.91 and 5.1.47 with serious security fixes, so we provide binary releases of Percona Server 5.0 and Percona Server / XtraDB 5.1 with security patches. Fixed bugs: Bug#53371, CVE-2010-1848 Bug#53237, CVE-2010-1850 Bug#50974, CVE-2010-1849 Release Percona Server 5.0.91-rel22 is available in our download area: http://www.percona.com/downloads/Percona-Server-5.0/Percona-Server-5.0.91-22/ Release Percona Server/XtraDB 5.1.45-rel10.2 [...]
Blob Storage in Innodb
I’m running in this misconception second time in a week or so, so it is time to blog about it. How blobs are stored in Innodb ? This depends on 3 factors. Blob size; Full row size and Innodb row format. But before we look into how BLOBs are really stored lets see what misconception [...]
Upgrading MySQL
Upgrading MySQL Server is a very interesting task as you can approach it with so much different “depth”. For some this is 15 minutes job for others it is many month projects. Why is that ? Performing MySQL upgrade two things should normally worry you. It is Regressions – functionality regressions when what you’ve been [...]
Air traffic queries in MyISAM and Tokutek (TokuDB)
This is next post in series Analyzing air traffic performance with InfoBright and MonetDB Air traffic queries in LucidDB Air traffic queries in InfiniDB: early alpha Let me explain the reason of choosing these engines. After initial three posts I am often asked “What is baseline ? Can we compare results with standard MySQL engines [...]
Crashes while using MyISAM with multiple key caches
Over last couple of years I have ran into random MySQL crashes in production when multiple key caches were used. Unfortunately this never was frequent or critical enough issue so I could spend time creating repeatable test case and search of the bug in the MySQL database did not find anything. Recently we had this [...]
MySQL 5.1 went to GA. Was it a good move ?
MySQL 5.1 release as “GA” seems to be the most controversial to date. It had very negative response from Monty, original MySQL Founder and controversial responses in community including another beating by Kevin Burton. There is also very interesting reading on MySQL 5.1 open bugs So how do I take it and where do I [...]
Improved InnoDB rw_lock patch
There is patch from Google to improve SMP performance , but for some workloads it showed for us reverse scalability. E.g. update_key benchmark from sysbench. There are also results with Yasufumi’s rw_locks (http://bugs.mysql.com/bug.php?id=26442)
MySQL End Of Life (EOL) Policy
We’ve discussed today how we should implement MySQL Version advisory in mk-audit tool. One obvious questions was to look at the end of life – it is often bad idea to run MySQL versions past end of life as even security bugs may not be fixed in these (though do not get paranoid, if you’re [...]
MySQL Architecture meeting at Google
Friday after MySQL Users Conference we had a smaller meeting at Google campus to talk about MySQL architecture mainly focusing on storage engine vendors and other extension areas. It was very interesting to see all these storage engine interface extensions which are planned for MySQL 6.0 and beyond – abilities to intercept query execution or [...]

