The latest Percona Server release has one new feature: now MEMORY tables can have BLOB and TEXT columns, and VARCHAR columns will not waste space due to implicit extension to CHAR.
Drop table performance
April 20, 2011 By 22 Comments
There have been recent discussions about DROP TABLE performance in InnoDB. (You can refer to Peter’s post http://www.mysqlperformanceblog.com/2011/02/03/performance-problem-with-innodb-and-drop-table/ and these bug reports: http://bugs.mysql.com/bug.php?id=51325 and http://bugs.mysql.com/bug.php?id=56332.) It may not sound that serious, but if your workload often uses DROP TABLE and you have a big buffer pool, it may be a significant issue. This can get [...]
Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
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 [...]
MySQL Partitioning – can save you or kill you
December 11, 2010 By 44 Comments
I wanted for a while to write about using MySQL Partitioning for Performance Optimization and I just got a relevant customer case to illustrate it. First you need to understand how partitions work internally. Partitions are on the low level are separate table. This means when you’re doing lookup by partitioned key you will look [...]
Thinking about running OPTIMIZE on your Innodb Table ? Stop!
December 9, 2010 By 17 Comments
Innodb/XtraDB tables do benefit from being reorganized often. You can get data physically laid out in primary key order as well as get better feel for primary key and index pages and so using less space, it is just OPTIMIZE TABLE might not be best way to do it. If you’re running Innodb Plugin on [...]
The perils of uniform hardware and RAID auto-learn cycles
November 16, 2010 By 16 Comments
Last night a customer had an emergency in selected machines on a large cluster of quite uniform database servers. Some of the servers were slowing down in a very puzzling way over a short time span (a couple of hours). Queries were taking multiple seconds to execute instead of being practically instantaneous. But nothing seemed [...]
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. [...]
Percona Server 5.1.47-rel11.0
June 21, 2010 By 13 Comments
Dear Community, Percona Server version 5.1.47-rel11.0 is available for download now. The changes in this release include: New features Percona Server is now based on MySQL 5.1.47, and XtraDB is now based on InnoDB plugin 1.0.8. XtraDB now uses the fast recovery code released in InnoDB Plugin version 1.0.8, instead of Percona’s earlier fast-recovery code. [...]
Purge Thread Spiral of Death
June 10, 2010 By 5 Comments
I just wrote a large post on reasons for innodb main tablespace excessive growth and I thought it would make sense to explain briefly of why it is so frequently you have purge not being the problem at all and when out of no where you can see purge thread being unable to keep up [...]
Reasons for run-away main Innodb Tablespace
June 10, 2010 By 2 Comments
So you’re running MySQL With innodb_file_per_table option but your ibdata1 file which holds main (or system) tablespace have grown dramatically from its starting 10MB size. What could be the reason of this growth and what you can do about it ? There are few things which are always stored in main tablespace – these are [...]
