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 [...]
Recovery beyond data restore
August 2, 2008 By 11 Comments
Quite frequently I see customers looking at recovery as on ability to restore data from backup which can be far from being enough to restore the whole system to operating state, especially for complex systems. Instead of looking just at data restore process you better look at the whole process which is required to bring [...]
How much overhead DRDB could cause ?
June 2, 2008 By 4 Comments
I was working with the customer today investigating MySQL over DRBD performance issues. His basic question was why there is so much overhead with DRBD in my case, while it is said there should be no more than 30% overhead when DRBD is used. The truth is – because how DRBD works it does not [...]
Is disk Everything for MySQL Performance ?
April 25, 2008 By 7 Comments
I read very nice post by Matt today and it has many good insights though I can’t say I agree on all points. First there is a lot of people out where which put it as disk is everything. Remember Paul Tuckfield saying “You should ask how many disks they have instead of how many [...]
Choosing innodb_buffer_pool_size
November 3, 2007 By 39 Comments
My last post about Innodb Performance Optimization got a lot of comments choosing proper innodb_buffer_pool_size and indeed I oversimplified things a bit too much, so let me write a bit better description. Innodb Buffer Pool is by far the most important option for Innodb Performance and it must be set correctly. I’ve seen a lot [...]
MySQL 4 to MySQL 5 Upgrade performance regressions
June 6, 2007 By 8 Comments
This week I already had two serious performance regression cases when upgrading from MySQL 4.0 and 4.1 to MySQL 5.0. By serious I mean several times performance difference not just 5-10% you often see for simple queries due to generally fatter code. The problem in both cases was MySQL 5.0 broken group commit bug. First [...]
How to estimate time it takes Innodb to Recover ?
May 9, 2007 By 7 Comments
Today seems to be Innodb day in our Blog, but well this is the question which pops ups quite frequently in Innodb talks and during consulting engagements. It is well known to get better performance you should normally set innodb_log_file_size large. We however usually recommend caution as it may significantly increase recovery time if Innodb [...]
Jeremy Cole on MySQL Replication
May 27, 2006 By 12 Comments
Jeremy Cole recently posted very nice post about MySQL Replication Performance. There are however few points I should comment on. Jeremy Speaks about MyISAM and Innodb in the same terms, in fact they are quite different for Replication. As you probably know MyISAM uses buffered IO so if master crashes you’re out of sync anyway [...]
