Recently, Morgan has been writing on deprecating some MySQL features and inspired by that while working on MySQL on POWER, I wondered “What is the impact of the MySQL query cache on modern hardware?”

We’ve known for over six years (since before we started Drizzle) that the query cache hurt performance. It was for that reason that the query cache was one of the early things to be removed from Drizzle, it just didn’t scale on multi core systems that  we were targeting.

So what about modern hardware? While working on MySQL 5.6 on POWER8, I enabled the query cache and ran a benchmark. …

How To Install Nginx With PHP5 (And PHP-FPM) And MySQL Support On CentOS 6.5

Nginx(pronounced "engine x") is a free, open-source, high-performance HTTP server. Nginx is known for its stability, rich feature set, simple configuration, and low resource consumption. This tutorial shows how you can install Nginx on a CentOS 6.5 server with PHP5 support (through PHP-FPM) and MySQL support.

There will be 2 community meetups in Tokyo in Japan scheduled for June 2014. Please check and join following: 

• MySQL Casual Talks vol.6
  • Date: June 11th, 2014
  • Time: 19:00
  • Place: Oracle office, Oracle Aoyama Center, 2-5-8 Kita-Aoyama, Minato-ku, Tokyo, Japan
  • More info & Registration
• MySQL Cluster Casual Talk #2
  • Date: June 25th, 2014
  • Time: 19:00
  • Place: GMO Yours, …

We recently open-sourced our percona-agent and if you check out the source code, you’ll find that it is written in the Go programming language (aka Golang). For those not up to speed, the percona-agent is a real-time client-side agent for Percona Cloud Tools.

Our requirements are quite demanding for our agents. This one is software that works on a real production server, so it must be fast, reliable, lightweight and easy to distribute. Surprisingly enough, binaries compiled by Go fit these characteristics.

There are of course alternatives that we considered. On the scripting side: Perl, Python, PHP, Ruby et al. These are not necessarily fast, and the distribution is also interesting. We have enough experience with …

Percona is glad to announce the release of Percona Toolkit 2.2.8 on June 4th, 2014 (Downloads are available here and from the Percona Software Repositories). This release is the current GA (Generally Available) stable release in the 2.2 series.

New Features:

• pt-agent has been replaced by percona-agent. More information on percona-agent can be found in the Introducing the 3-Minute MySQL Monitor …

MariaDB has plenty of mirrors to download the latest versions of MariaDB. Typically mirrors carry the last couple of releases and the current release, but what if you wanted to access something much older?

You have two resources for the complete archive:

1. http://archive.mariadb.org/ – this is the official archive, but from what I gather, it can be quite slow
2. http://downloads.skysql.com/files/MariaDB/ – SkySQL provides a complete mirror and it is very fast so I would use this instead. 

Current download archives stand at 337GB. But you can …

Using MySQL Sandbox I can install multiple instances of MySQL. It is not uncommon for me to run 5 or 6 instances at once, and in some occasions, I get to have even 10 of them. It is usually not a problem. But today I had an issue while testing MariaDB, for which I needed 5 instances, and I the installation failed after the 4th one. To make sure that the host could run that many servers, I tried installing 10 instances of MySQL 5.6 and 5.7. All at once, for a grand total of 20 instances:

$ make_multiple_sandbox --how_many_nodes=10 5.6.14
installing node 1
installing node 2
installing node 3
installing node 4
installing node 5
installing node 6
installing node 7
installing node 8
installing node 9
installing node 10
group directory installed in $HOME/sandboxes/multi_msb_5_6_14
$ make_multiple_sandbox --how_many_nodes=10 5.7.4 …

Changes (as compared to 5.72) include:

Features:
* The MONyog API is enhanced with more options to manage servers registered in MONyog. Options now include calls to add/edit/remove servers. Refer documentation for full details.
* MONyog now supports Query analysis using Performance Schema tables (events_statements_summary_by_digest and events_statements_history_long tables). This feature is supported only for MySQL 5.6.14 and MariaDB 10.0 and above.
* Explain plan is available in Query analyzer for Slow_log table based logging and Processlist sniffer.
* An example query is now shown in detailed query view in Query analyzer if queries replaced with literals is selected.
* MONyog now has a configurable option to define the max. query length displayed. …

I’ve been running a benchmark today on my old test box with conventional hard drives (no raid with BBU) and noticed something unusual in the CPU utilization statistics being reported.

The benchmark was run like this:

sysbench --num-threads=64 --max-requests=0 --max-time=600000 --report-interval=10 --test=oltp --db-driver=mysql --oltp-dist-type=special  --oltp-table-size=1000000   --mysql-user=root --mysql-password=password  run

Which means: create 64 threads and hammer the database with queries as quickly as possible. As the test was run on the localhost I would expect the benchmark to completely saturate the system – being either using CPU or being blocked on IO nature of this benchmark so it does not spend a lot on database locks, especially as this system has just 2 cores.

Looking at VMSTAT however I noticed this:

[root@smt1 mysql]# vmstat 10
procs -----------memory---------- ---swap-- -----io---- …

Percona is glad to announce the release of Percona Server 5.5.37-35.1 on June 3rd, 2014 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.37, including all the bug fixes in it, Percona Server 5.5.37-35.1 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 can be found in the  …