November 1, 2014

MySQL Upgrade Webinar Questions Followup

I did a Webinar about MySQL Upgrade – Best Practices Yesterday and there were some questions we could not answer during Webinar, following Jay’s Lead I decided to post them as a Blog Post. Q: Can you go directly MySQL 5.0 to 5.5 for MyISAM tables? MyISAM have not been getting any significant development since […]

The story of one MySQL Upgrade

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 […]

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 […]

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 […]

More Gotchas with MySQL 5.0

Working on large upgrade of MySQL 4.1 running Innodb to MySQL 5.0 and doing oprofile analyzes we found very interesting issue of buf_get_latched_pages_number being responsible for most CPU usage. It did not look right. The close look revealed this is the function which is used to compute number of latched pages in Innodb Buffer Pool, […]

MySQL 4 to MySQL 5 Upgrade performance regressions

This week I already had two serious performance regression cases when upgrading from MySQL 4.0 and 4.1 to MySQL 5.0. By serious I mean several times performance difference not just 5-10% you often see for simple queries due to generally fatter code. The problem in both cases was MySQL 5.0 broken group commit bug. First […]

MySQL Installation and upgrade scripts.

I generally find MySQL Sever sufficiently tested, meaning at least minor version upgrades rarely cause the problems. Of course it is not perfect and I remember number of big issues when some releases could not be used due to behavior changes in them and when something had to be rolled back in the next release. […]

Even minor upgrades are not always safe

I already wrote couple of weeks ago I keep most of my systems on MySQL 4.1 still as they will not benefit from MySQL 5.0 features anyway while I do not want to likely loose a bit of performance and possibly deal with new bugs and changes introduced in MySQL 5.0 (You never know where […]

MySQL Server Upgrade

Today I’ve upgraded MySQL Server on the host running MySQL Performance Blog. MySQL 4.1.12 was running here for well over a year before that. Why Have not I upgraded before ? Well because it just worked fine. Yes I know there were some security fixes but I have dedicated server with remote MySQL access closed […]

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 […]