I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the Percona documentation or forums. So I present to you what is now my newest Firefox toolbar bookmark: an option and [...]
Data mart or data warehouse?
July 15, 2010 By 13 Comments
This is part two in my six part series on business intelligence, with a focus on OLAP analysis. Part 1 – Intro to OLAP Identifying the differences between a data warehouse and a data mart. (this post) Introduction to MDX and the kind of SQL which a ROLAP tool must generate to answer those queries. [...]
On Good Instrumentation
May 31, 2010 By 1 Comment
In so many cases troubleshooting applications I keep thinking how much more efficient things could be going if only there would be a good instrumentation available. Most of applications out there have very little code to help understand what is going on and if it is there it is frequently looking at some metrics which [...]
“Shard early, shard often”
November 16, 2009 By 6 Comments
I wrote a post a while back that said why you don’t want to shard. In that post that I tried to explain that hardware advances such as 128G of RAM being so cheap is changing the point at which you need to shard, and that the (often omitted) operational issues created by sharding can [...]
Just do the math!
July 6, 2009 By 4 Comments
One of the most typical reasons for performance and scalability problems I encounter is simply failing to do the math. And these are typically bad one because it often leads to implementing architectures which are not up for job they are intended to solve. Let me start with example to make it clear. Lets say [...]
Detailed review of Tokutek storage engine
April 28, 2009 By 21 Comments
(Note: Review was done as part of our consulting practice, but is totally independent and fully reflects our opinion) I had a chance to take look TokuDB (the name of the Tokutek storage engine), and run some benchmarks. Tuning of TokuDB is much easier than InnoDB, there only few parameters to change, and actually out-of-box [...]
Computing 95 percentile in MySQL
November 28, 2008 By 5 Comments
When doing performance analyzes you often would want to see 95 percentile, 99 percentile and similar values. The “average” is the evil of performance optimization and often as helpful as “average patient temperature in the hospital”. Lets set you have 10000 page views or queries and have average response time of 1 second. What does [...]
Tools
May 30, 2008 By 31 Comments
This page contains links to various tools we found helpful to use in practice. Some tools are written by us, others by third parties, yet another ones may be shipped with your operating system you just need to find they are there. Percona Toolkit Percona Toolkit is a great set of tools for MySQL Performance [...]
MySQL extensions for hosting
April 24, 2008 By 11 Comments
A few weeks ago I was asked to isolate some functionalities from Mark Callaghan’s MySQL patch bundle. They were extensions adding per-user and per-table accounting to the database, accessible with a new set of commands such as SHOW TABLE_STATISTICS, SHOW INDEX_STATISTICS and SHOW USER_STATISTICS. The first two can interest anyone to periodically check what data [...]
Finding out largest tables on MySQL Server
February 4, 2008 By 27 Comments
Finding largest tables on MySQL instance is no brainier in MySQL 5.0+ thanks to Information Schema but I still wanted to post little query I use for the purpose so I can easily find it later, plus it is quite handy in a way it presents information:
