April 21, 2014

Analyzing Slow Query Table in MySQL 5.6

Next week I’m teaching an online Percona Training class, called Analyzing SQL Queries with Percona Toolkit.  This is a guided tour of best practices for pt-query-digest, the best tool for evaluating where your database response time is being spent. This month we saw the GA release of MySQL 5.6, and I wanted to check if any […]

How to use tcpdump on very busy hosts

Often I run into problems when trying to use mk-query-digest with tcpdump on “very” busy hosts. You might be thinking, “very busy is a relative and unquantifiable term,” and you’d be right, so I’ll phrase this differently. Let me give a little background to the problem first. Mk-query-digest tries to handle dropped or missing packets […]

Logging MySQL queries from the client instead of the server

The “slow query log” is the single most valuable way to examine query execution on your MySQL server. Queries are logged with timing information, and in the case of Percona Server, a great deal of additional performance and other diagnostic information. But the execution time recorded in the log is the time the query took […]

Gathering queries from a server with Maatkit and tcpdump

For the last couple of months, we’ve been quietly developing a MySQL protocol parser for Maatkit. It isn’t an implementation of the protocol: it’s an observer of the protocol. This lets us gather queries from servers that don’t have a slow query log enabled, at very high time resolution. With this new functionality, it becomes […]

Poor man’s query logging

Occasionally there is a need to see what queries reach MySQL. The database provides several ways to share that information with you. One is called general log activated with

(or

in MySQL 5.1+) start-up parameter. The log writes any query being executed by MySQL to a file with limited amount of additional information. […]

Updated msl (microslow) patch, installation walk-through!

For a couple of months there have been no updates to our msl patch, however recently I managed some time to change this. The functionality was extended a little bit and what’s even more important the patch is available for all the recent MySQL releases. To remind anyone who has not yet come across this […]

Slow Query Log analyzes tools

(There is an updated version of this post here). MySQL has simple but quite handy feature – slow query log, which allows you to log all queries which took over define number of seconds to execute. There is also an option to enable logging queries which do not use indexes even if they take less […]

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 […]

Percona Server 5.5.34-32.0 is now available

Percona is glad to announce the release of Percona Server 5.5.34-32.0 on October 28th, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.34, including all the bug fixes in it, Percona Server 5.5.34-32.0 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release […]

Tuning MySQL 5.6 configuration – Webinar followup

We had a wonderful time during the Sept. 25 webinar, “MySQL 5.6 Configuration Optimization,” and I got a lot more questions than I could answer during the hour. So here is a followup with answers to the most interesting questions you guys asked. (You can also watch a recording of entire webinar here.) Q: What […]