July 30, 2014

A technical WebScaleSQL review and comparison with Percona Server

The recent WebScaleSQL announcement has made quite a splash in the MySQL community over the last few weeks, and with a good reason. The collaboration between the major MySQL-at-scale users to develop a single code branch that addresses the needs of, well, web scale, is going to benefit the whole community. But I feel that […]

Percona Server 5.6.15-63.0 is now available

Percona is glad to announce the release of Percona Server 5.6.15-63.0 on December 19th, 2013 (Downloads are available here and from the Percona Software Repositories. Based on MySQL 5.6.15, including all the bug fixes in it, Percona Server 5.6.15-63.0 is the current GA release in the Percona Server 5.6 series. All of Percona’s software is […]

Is Synchronous Replication right for your app?

I talk with lot of people who are really interested in Percona XtraDB Cluster (PXC) and mostly they are interested in PXC as a high-availability solution.  But, what they tend not to think too much about is if moving from async to synchronous replication is right for their application or not. Facts about Galera replication […]

MySQL 5.5 and MySQL 5.6 default variable values differences

As the part of analyzing surprising MySQL 5.5 vs MySQL 5.6 performance results I’ve been looking at changes to default variable values. To do that I’ve loaded the values from MySQL 5.5.30 and MySQL 5.6.10 to the different tables and ran the query:

Lets go over to see what are the most important changes […]

Distributed Set Processing with Shard-Query

Can Shard-Query scale to 20 nodes? Peter asked this question in comments to to my previous Shard-Query benchmark. Actually he asked if it could scale to 50, but testing 20 was all I could due to to EC2 and time limits. I think the results at 20 nodes are very useful to understand the performance: […]

Ultimate MySQL variable and status reference list

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 […]

The perils of InnoDB with Debian and startup scripts

Are you running MySQL on Debian or Ubuntu with InnoDB? You might want to disable /etc/mysql/debian-start. When you run /etc/init.d/mysql start it runs this script, which runs mysqlcheck, which can destroy performance. It can happen on a server with MyISAM tables, if there are enough tables, but it is far worse on InnoDB. There are […]

Goal driven performance optimization

When your goal is to optimize application performance it is very important to understand what goal do you really have. If you do not have a good understanding of the goal your performance optimization effort may well still bring its results but you may waste a lot of time before you reach same results as […]

MySQL 5.0, 5.1 and Innodb Plugin CPU Efficiency

We’ve recently done benchmarks comparing different MySQL versions in terms of their CPU efficiently in TPC-C like Workload. We did it couple of weeks ago so MySQL 5.0.67, MySQL 5.1.29 and Innodb Plugin 1.0.1 were used which are not very recent, though we do not think results will differ a lot with today versions.

InnoDB thread concurrency

InnoDB has a mechanism to regulate count of threads working inside InnoDB. innodb_thread_concurrency is variable which set this count, and there are two friendly variables innodb_thread_sleep_delay and innodb_concurrency_tickets. I’ll try to explain how it works. MySQL has pluginable architecture which divides work between mysql common code (parser, optimizer) and storage engine. From storage engine’s point […]