Percona is glad to announce the release of Percona Server 5.5.16-22.0 on October 14, 2011 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.16, including all the bug fixes in it, Percona Server 5.5.16-22.0 is now the current stable release in the 5.5 series. All of Percona’s software is open-source and free, all the [...]
Infinite Replication Loop
October 10, 2011 By 2 Comments
Last week I helped 2 different customers with infinite replication loops. I decided to write a blog post about these infinite loop of binary log statements in MySQL Replication. To explain what they are, how to identify them… and how to fix them.
Flexviews – part 3 – improving query performance using materialized views
April 4, 2011 By 20 Comments
Combating “data drift” In my first post in this series, I described materialized views (MVs). An MV is essentially a cached result set at one point in time. The contents of the MV will become incorrect (out of sync) when the underlying data changes. This loss of synchronization is sometimes called drift. This is conceptually [...]
Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
There are many angles you can look at the system to predict in performance, the model baron has published for example is good for measuring scalability of the system as concurrency growths. In many cases however we’re facing a need to answer a question how much load a given system can handle when load is [...]
The story of one MySQL Upgrade
October 8, 2010 By 8 Comments
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 [...]
Why you should ignore MySQL’s key cache hit ratio
February 28, 2010 By 28 Comments
I have not caused a fist fight in a while, so it’s time to take off the gloves. I claim that somewhere around of 99% of advice about tuning MySQL’s key cache hit ratio is wrong, even when you hear it from experts. There are two major problems with the key buffer hit ratio, and [...]
Multi Column indexes vs Index Merge
September 19, 2009 By 31 Comments
The mistake I commonly see among MySQL users is how indexes are created. Quite commonly people just index individual columns as they are referenced in where clause thinking this is the optimal indexing strategy. For example if I would have something like AGE=18 AND STATE=’CA’ they would create 2 separate indexes on AGE and STATE [...]
A rule of thumb for choosing column order in indexes
June 5, 2009 By 15 Comments
I wanted to share a little rule of thumb I sometimes use to decide which columns should come first in an index. This is not specific to MySQL, it’s generally applicable to any database server with b-tree indexes. And there are a bunch of subtleties, but I will also ignore those for the sake of [...]
Why MySQL’s binlog-do-db option is dangerous
May 14, 2009 By 15 Comments
I see a lot of people filtering replication with binlog-do-db, binlog-ignore-db, replicate-do-db, and replicate-ignore-db. Although there are uses for these, they are dangerous and in my opinion, they are overused. For many cases, there’s a safer alternative.
How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
Our customers or prospective customers often ask us how we do a performance audit (it’s our most popular service). I thought I should write a blog post that will both answer their question, so I can just reply “read all about it at this URL” and share our methodology with readers a little bit. This [...]
