MySQL 5.6.7 RC is there, so I decided to test how it performs in tpcc-mysql workload from both performance and stability standpoints. I can’t say that my experience was totally flawless, I bumped into two bugs: MySQL 5.6.7 locks itself on CREATE INDEX MySQL 5.6.7-rc crashed under tpcc-mysql workload But at the end, is not [...]
ALTER TABLE: Creating Index by Sort and Buffer Pool Size
June 27, 2012 By 4 Comments
Today I was looking at the ALTER TABLE performance with fast index creation and without it with different buffer pool sizes. Results are pretty interesting. I used modified Sysbench table for these tests because original table as initially created only has index on column K which initially contains only zeros, which means index is very [...]
Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
Overview Profiling, analyzing and then fixing queries is likely the most oft-repeated part of a job of a DBA and one that keeps evolving, as new features are added to the application new queries pop up that need to be analyzed and fixed. And there are not too many tools out there that can make [...]
Improved InnoDB fast index creation
November 6, 2011 By 4 Comments
One of the serious limitations in the fast index creation feature introduced in the InnoDB plugin is that it only works when indexes are explicitly created using ALTER TABLE or CREATE INDEX. Peter has already blogged about it before, here I’ll just briefly reiterate other cases that might benefit from that feature: when ALTER TABLE [...]
Innodb row size limitation
April 7, 2011 By 12 Comments
I recently worked on a customer case where at seemingly random times, inserts would fail with Innodb error 139. This is a rather simple problem, but due to it’s nature, it may only affect you after you already have a system running in production for a while.
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 [...]
Innodb undo segment size and transaction isolation
January 12, 2011 By 3 Comments
You might know if you have long running transactions you’re risking having a lot of “garbage” accumulated in undo segment size which can cause performance degradation as well as increased disk space usage. Long transactions can also be bad for other reasons such as taking row level locks which will prevent other transactions for execution, [...]
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 [...]
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 [...]
Paul McCullagh answers your questions about PBXT
November 20, 2009 By 2 Comments
Following on from our earlier announcement, Paul McCullagh has responded with the answers to your questions – as well as a few I gathered from other Percona folks, and attendees of OpenSQL Camp. Thank you Paul! What’s the “ideal” use case for the PBXT engine, and how does it compare in performance?  When would I [...]
