April 19, 2014

MySQL server memory usage troubleshooting tips

There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory usage for MySQL. As a Percona support engineer, I’m seeing many issues regularly related to heavy server loads – OR OOM killer got invoked and […]

Analyzing WordPress MySQL queries with Query Analytics

This blog, MySQLPerformanceBlog.com, is powered by WordPress, but we never really looked into what kind of queries to MySQL are used by WordPress. So for couple months we ran a Query Analytics (part of Percona Cloud Tools) agent there, and now it is interesting to take a look on queries. Query Analytics uses reports produced […]

Increasing slow query performance with the parallel query execution

MySQL and Scaling-up (using more powerful hardware) was always a hot topic. Originally MySQL did not scale well with multiple CPUs; there were times when InnoDB performed poorer with more  CPU cores than with less CPU cores. MySQL 5.6 can scale significantly better; however there is still 1 big limitation: 1 SQL query will eventually use only […]

Renaming database schema in MySQL

One of the routine tasks for a DBA is renaming database schemas, and as such MySQL added a command to carry out that purpose called “RENAME DATABASE <database_name>”. However this command just made it through a few minor releases before being discontinued (from MySQL 5.1.7 to 5.1.23). Here’s a link to the reference manual regarding […]

A sneak peek at the Percona Live MySQL Conference & Expo 2014

MySQL gurus from Oracle, Facebook, Google, LinkedIn, Twitter, Yelp (and more) have submitted papers and will speak at the third annual Percona Live MySQL Conference and Expo 2014 in sunny Santa Clara, California this coming April 1-4. If you attended last April’s Percona Live MySQL Conference and Expo – and/or last month’s Percona Live London […]

Download insightful MySQL presentations from Percona Live London 2013

The MySQL community came together last month for two days of outstanding technical tutorials and sessions at Percona Live London. And now many of those MySQL presentations are available for free download. This year’s London conference saw a 20 percent spike in attendance compared with last year, with MySQL professionals from 31 countries gathering in […]

MySQL Error: Too many connections

We have always received quite few questions here at Percona Support on how to avoid the dreaded “Too many connections” error, as well as what is the recommended value for max_connections. So, in this article I will try to cover best possible answers to these questions so others can mitigate similar kinds of issues. My […]

Percona Live London 2013 and Percona Live MySQL Conference & Expo 2014

Thanks to everyone who participated in Percona Live London 2013. We had a great event with nearly 20% higher attendance versus 2012. This year’s conference featured participation by representatives from Oracle including a compelling keynote by Tomas Ulin. The conference featured 10 tutorial sessions on Monday and 4 keynotes and 30 breakout sessions on Tuesday. […]

How to recover an orphaned .ibd file with MySQL 5.6

A few years ago Yves Trudeau and Aleksandr Kuzminsky wrote posts about different ways for recovering orphaned .ibd files: Connecting orphaned .ibd files A recovery trivia or how to recover from a lost ibdata1 file Today I want to show you how to do that in more easy and quick way. In my example I’ll […]

The power of MySQL’s GROUP_CONCAT

In the very early days of Percona Vadim wrote very nice post about GROUP_CONCAT. But I want to show you a bit more about it. When is GROUP_CONCAT useful? Usually while working with Support customers I recommend it when you have aggregation of many-to-many info. It makes the view simpler and more beautiful and it […]