Percona is glad to announce the release of Percona Server 5.1.66-14.1 on October 26th, 2012 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.1.66, including all the bug fixes in it, Percona Server 5.1.66-14.1 is now the current stable release in the 5.1 series. All of Percona‘s software is open-source and free, all the details of the release can [...]
Troubleshooting MySQL Upgrade Performance Regressions
February 15, 2012 By Leave a Comment
So lets say you upgraded from MySQL 5.1 to Percona Server 5.5 and instead of expected performance improvement you see your performance being worse. What should you do ? First if you followed MySQL upgrade best practices such as testing your workload with pt-upgrade the chances of this happening are rather slim. But lets assume [...]
MySQL Life Cycle. Your Feedback is needed.
November 18, 2011 By 6 Comments
When I started with MySQL 3.22 I would start running MySQL from early beta (if not alpha) and update MySQL the same date as release would hit the web. Since that time I matured and so did MySQL ecosystem. MySQL is powering a lot more demanding and business critical applications now than 12 years ago [...]
Percona Server 5.1.59-13.0
October 16, 2011 By Leave a Comment
Percona is glad to announce the release of Percona Server 5.1.59-13.0 on October 15, 2011 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.1.59, including all the bug fixes in it, Percona Server 5.1.59-13.0 is now the current stable release in the 5.1 series. All of Percona’s software is open-source and free, all the [...]
When EXPLAIN estimates can go wrong!
October 13, 2011 By 7 Comments
I have been working with a few customer cases and one interesting case popped up. The customer was facing a peculiar problem where the rows column in the EXPLAIN output of the query was totally off. The actual number of rows was 18 times more than the number of rows reported by MySQL in the [...]
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 [...]
Air traffic queries in MyISAM and Tokutek (TokuDB)
November 5, 2009 By 26 Comments
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 [...]
High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
We have a lot of customers who do click analysis, site analytics, search engine marketing, online advertising, user behavior analysis, and many similar types of work. The first thing these have in common is that they’re generally some kind of loggable event. The next characteristic of a lot of these systems (real or planned) is [...]
Recovering CREATE TABLE statement from .frm file
December 17, 2008 By 5 Comments
So lets say you have .frm file for the table and you need to recover CREATE TABLE statement for this table. In particular when we do Innodb Recovery we often get .frm files and some mess in the Innodb tablespace from which we have to get data from. Of course we could relay on old [...]
MySQL 6.0 vs 5.1 in TPC-H queries
March 25, 2008 By 17 Comments
Last week I played with queries from TPC-H benchmarks, particularly comparing MySQL 6.0.4-alpha with 5.1. MySQL 6.0 is interesting here, as there is a lot of new changes in optimizer, which should affect execution plan of TPC-H queries. In reality only two queries (from 22) have significantly better execution time (about them in next posts), [...]
