This post is a step-by-step guide to set up Percona XtraDB Cluster (PXC) in a virtualized test sandbox. I used Amazon EC2 micro instances, but the content here is applicable for any kind of virtualization technology (for example VirtualBox). The goal is to give step by step instructions, so the setup process is understandable and it could serve as a reference architecture.

You will need 4 virtual machines. 3 for PXC and 1 for the client, which will have HaProxy. I used CentOS 6 as the operating system, the instructions are similar for any Linux distribution.

The client node will have HaProxy installed and it will redirect requests to PXC nodes. This approach works well in real-world scenarios too. Running HaProxy on the application servers instead of having them as dedicated entities gives you benefits like you don’t need an extra network roundtrip because of a loadbalancer and scalability of PXC’s load balancing layer scales …

Contrary to initial reports here and here, further investigation has revealed that under some specific and limited circumstances, Percona Server and Percona XtraDB Cluster binaries, similar to other MySQL variants, are susceptible to the security vulnerability in MySQL/MariaDB sql/password.c:

• 64bit Ubuntu Oneiric (11.10) binaries are vulnerable in Percona Server ONLY on some hardware/virtualization platforms (confirmed on Amazon EC2 but not on HP Cloud).
• Neither older nor newer Ubuntu versions are affected.
• Oneiric is not a LTS distribution. Most …

Version 1.0.1 of the Percona Monitoring Plugins is released. This is a routine bug-fix release that addresses several minor issues.

The Percona Monitoring Plugins are high-quality components to add enterprise-grade MySQL monitoring and graphing capabilities to your existing in-house, on-premises monitoring solutions. The components are designed to integrate seamlessly with widely deployed solutions such as Nagios and Cacti, and are delivered in the form of templates, plugins, and scripts.

The plugins are fully supported for customers with a Percona Support contract, and free installation services are provided as part of some contracts. You can find links to downloads, …

The Percona Toolkit team is happy to announce the release of Percona Toolkit versions 2.0.5 and 2.1.2. These are bug-fix releases in the 2.0 and 2.1 series, respectively. These releases fix many dozens of bugs, and we suggest that users upgrade to the latest versions of the tools.

The complete list of changes is on Launchpad for 2.0.5 and 2.1.2. Here are some highlights of the changes in version 2.1.2, which is the current development focus:

• We fixed several bugs in pt-table-sync that prevented it from working properly, and disabled the –lock-and-rename feature when using it with MySQL versions that don’t support it reliably.
• We enhanced pt-table-checksum and pt-online-schema-change to add even more safety checks, and to detect and deal with …

Many of you heard of this nasty security vulnerability in MySQL, and as we are getting a lot of inquiries how does it affect Percona Server, I decided to address it in this post.

• The issue exists in the source code of MySQL 5.5.23 or earlier and MySQL 5.1.62 or earlier. The same is true for Percona Server, as we share the same code base.
• However binaries provided by Percona do not have this problem, as in our build process we do not use sse-optimized glibc memcmp. This is true for any version of Percona and all tar.gz, RPM and DEB packages. Once again, if you use binary builds, provided by Percona from our official download area, or from our repositories, you are safe.
• If you use your own or third-party binaries, …

I am happy to announce next version Percona XtraDB Cluster 5.5.24, which is mostly jump to the current version of Percona Server.

It includes an important bug fix:

• table with no PK but still having UK, can cause crash in slave using PA

Binaries are available from downloads area or from our repositories.

For this release we provide binaries for Ubuntu 12.04.

If you want to know more how to migrate to XtraDB Cluster, you can check our recent webinar Migrating To Percona XtraDB Cluster.

This is an General Availability release. We did our best to eliminate bugs and problems during alpha and …

One of our customers asked me whether it’s safe to enable the so-called USER_STATISTICS features of Percona Server in a heavy-use production server with many tens of thousands of tables.

If you’re not familiar with this feature, it creates some new INFORMATION_SCHEMA tables that add counters for activity on users, hosts, tables, indexes, and more. This is very helpful information. It lets you run queries to see which tables get the most reads and writes, for example. Another popular use for it is to find unused indexes.

I knew that some of our customers were using the feature enabled in production all the time, and I knew that Google and Facebook and others (the original developers) did also. But I didn’t know the …

Have you wanted to compress only certain types of columns in a table while leaving other columns uncompressed? While working on a customer case this week I saw an interesting problem where a table had many heavily utilized TEXT fields with some read queries exceeding 500MB (!!), and stored in a 100GB table. In this case we were not allowed to make any query or application logic changes so we chose to implement the Barracuda file format and utilize compressed rows as this appealed to me for this mostly-read application. One quick way you can see if your rows will benefit from compression would be to read Peter Zaitsev’s blog post and execute:

SELECT AVG(LENGTH((`colTextField`)) FROM `t1` WHERE `id` < 1000

compare this to:

SELECT AVG(LENGTH(COMPRESS(`colTextField`))) FROM `t1` WHERE `id` < …

Percona is glad to announce the release of Percona Server 5.1.63-13.4 on May 24th, 2012 (Downloads are available from Percona Server 5.1.63-13.4 downloads and from the Percona Software Repositories).

Based on MySQL 5.1.63, including all the bug fixes in it, Percona Server 5.1.63-13.4 is now the current stable release in the 5.1 series. All of Percona‘s software is open-source and free, all the details of the release can be found in the 5.1.63-13.4 milestone at Launchpad.

Bugs fixed:

Our previous GA release of Percona XtraDB Cluster caused a lot of interest and feedback. I am happy to announce next version Percona XtraDB Cluster 5.5.23, which comes with bug fixes and improvements.

List of changes:

• Fixes merged from upstream (Codership-mysql)
• Support for MyISAM, now changes to MyISAM tables are replicated to other nodes
• Improvements to XtraBackup SST methods, better error handling
• New SST wsrep_sst_method=skip, useful when you start all nodes from the same sources (i.e. backup)
• Ability to pass list of IP addresses for a new node, it will connect to the first available

Binaries are available from downloads area or from our repositories.

For …