October 25, 2014

What kind of queries are bad for MySQL?

In writing a recommendation for our Web development team on how to use MySQL, I came up with the following list, which I want to share: What kind of queries are bad for MySQL? Any query is bad. Send a query only if you must. (Hint: use caching like memcache or redis) Queries that examine […]

Schema changes – what’s new in MySQL 5.6?

Among many of the improvements you can enjoy in MySQL 5.6, there is one that addresses a huge operational problem that most DBAs and System Administrators encounter in their life: schema changes. While it is usually not a problem for small tables or those in early stages of product life cycle, schema changes become a […]

MySQL Query Patterns, Optimized – Webinar questions followup

On Friday I gave a presentation on “MySQL Query Patterns, Optimized” for Percona MySQL Webinars.  If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions.  I answered as many as we had time for  during the session, but here […]

Percona Server for MySQL 5.5.30-30.2 now available

Percona is glad to announce the release of Percona Server for MySQL 5.5.30-30.2 on April 10, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.30, including all the bug fixes in it, Percona Server 5.5.30-30.2 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of […]

Announcing Percona Server for MySQL version 5.1.67-14.4

Percona is glad to announce the release of Percona Server for MySQL version 5.1.67-14.4 on March 8, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.1.67, including all the bug fixes in it, Percona Server 5.1.67-14.4 is now the current stable release in the 5.1 series. All of Percona‘s software is open-source and free, all the details […]

Investigating MySQL Replication Latency in Percona XtraDB Cluster

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 […]

Announcing Percona Server for MySQL version 5.5.29-30.0

Percona is glad to announce the release of Percona Server for MySQL version 5.5.29-30.0 on February 26th, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.29, including all the bug fixes in it, Percona Server 5.5.29-30.0 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details […]

Is there room for more MySQL IO Optimization?

I prefer to run MySQL with innodb_flush_method=O_DIRECT in most cases – it makes sure there is no overhead of double buffering and I can save the limited amount of file system cache I would normally have on database server for those things which need to be cached — system files, binary log, FRM files, MySQL […]

Review of MySQL 5.6 Defaults Changes

James Day just posted the great summary of defaults changes in MySQL 5.6 compared to MySQL 5.5 In general there are a lot of good changes and many defaults are now computed instead of hardcoded. Though some of changes are rather puzzling for me. Lets go over them: back_log = 50 + ( max_connections / […]

Adaptive flushing in MySQL 5.6 – cont

This is to continue my previous experiments on adaptive flushing in MySQL 5.6.6. Now I am running Ubuntu 12.04, which seems to provide a better throughput than previous system (CentOS 6.3), it also changes the profile of results. So, as previous I run tpcc-mysql 2500W, against MySQL 5.6.6 with innodb_buffer_pool_size 150GB, and now I vary […]