As part of Percona Remote DBA for MySQL service we recognize that reliable backups are one of the most important things we can bring to the table. In my experience handling emergencies, the single worst thing that can happen is finding out you don’t have backups available when some sort of data loss or catastrophic [...]
Investigating MySQL Replication Latency in Percona XtraDB Cluster
March 3, 2013 By 13 Comments
I was curious to check how Percona XtraDB Cluster behaves when it comes to MySQL replication latency — or better yet, call it data propagation latency. It was interesting to see whenever I can get stale data reads from other cluster nodes after write performed to some specific node. To test it I wrote quite a [...]
InnoDB compression woes
May 20, 2011 By 14 Comments
InnoDB compression is getting some traction, and I see quite contradictory opinions. Someone has successful deployments in productions, and someone says that compression in current implementation is useless. To get some initial impression about performance I decided to run some sysbench with multi-tables benchmarks. I actually was preparing to do complex research, but even first [...]
Percona Server and XtraBackup weekly news, February 19th
February 21, 2011 By 2 Comments
This week’s announcement is short: last week was pretty much all-hands-on-deck for our first 5.5.8 release. Still, it wasn’t ALL about the new release: The beta release of Percona Server 5.5.8 is out! More details in the release notes. There are ongoing discussions about parallel replication, as well as customer requests for enhancements to row-based [...]
RAID vs SSD vs FusionIO
May 1, 2009 By 17 Comments
In benchmarks passion (see my two previous posts) I managed to setup all three devices (RAID was on board; Intel X25-E SSD connected to HighPoint controller, FusionIO card) on our working horse Dell PowerEdge R900 (btw, to do that I had to switch from CentOS 5.2 to Ubuntu 8.10, as CentOS was not able to [...]
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 [...]
Quickly preloading Innodb tables in the buffer pool
May 1, 2008 By 9 Comments
In the previous post I mentioned a way I use to preload Clustered Index (data) for Innodb tables. Though I thought this topic would benefit from a bit more information. But lest first start with feature request for Innodb Team: All ways I mention here are hacks and they can’t be as efficient as native [...]
How multiple disks can benefit for single client workload ?
April 26, 2008 By 4 Comments
Let us talk few more about disks. You might have read my previous post and Matt’s Reply and it looks like there are few more things to clarify and explain. Before I get to main topic of the article lets comment on IO vs Disk question. If you look at Disk Based databases all data [...]
Can Innodb Read-Ahead reduce read performance ?
June 26, 2007 By 2 Comments
I ran into pretty interesting behavior today. We needed to dump and reload large database and we had pretty good IO subsystem so we started number of mysqldump processes in parallel. Unlike in other case when we did load in parallel, dump in parallel did not increase IO rate significantly and we could still see [...]
Using LoadAvg for Performance Optimization
December 4, 2006 By 5 Comments
Linux and Unixes have excellent metric of system load called “loadavg”. In fact load average is is 3 numbers which correspond to “load average” calculated for one five and 15 minutes. It is computed as exponential moving average so most recent load have more weight in the value than old one. What does Load Average [...]
