I’m proud to announce the GA release of version 2.1 of Percona Toolkit. Percona Toolkit is the essential suite of administrative tools for MySQL.
With this release we introduce a new version of pt-online-schema-change, a tool that enables you to ALTER large tables with no blocking or downtime. As you know, MySQL locks tables for most ALTER operations, but pt-online-schema-change performs the ALTER without any locking. Client applications can continue reading and writing the table with no interruption.
With this new version of the tool, one of the most painful things anyone experiences with MySQL is significantly alleviated. If you’ve ever delayed a project’s schedule because the release involved an ALTER, which had to be scheduled in the dead of the night on Sunday, and required overtime and time off, you know what I mean. A schema migration is an instant blocker in the critical path of your project plan. No more!
The pt-online-schema-change tool is not new to the toolkit. We developed it some time ago for a client and quietly included it, without knowing how much it would be used. We found that people were using it eagerly even without advertisement. However, it had many limitations and missing features. The new 2.1 version of the tool removes those limitations and makes the tool fully featured and much easier to use. The key is that it is replication-aware and inspects replicas, throttles its operation to avoid causing replication delay, watches for load on the master, and so forth. In this respect it is quite similar to pt-table-checksum, and it has all of the safeguards you might be familiar with from pt-table-checksum.
I will give a free webinar about the new pt-online-schema-change tool and how it enables zero-downtime schema changes on May 2nd.
In addition to pt-online-schema-change, we have completely redesigned and rebuilt the pt-summary and pt-mysql-summary tools. The changes are not so obvious to the user, but the benefit is that in the future we will be able to add features to these tools rapidly, for example, to support new types of RAID controllers.
Percona Toolkit is a hot topic at the upcoming MySQL Conference and there will be many talks about various parts of the toolkit:
The new Percona Toolkit release is available for download today. It is also in our YUM and DEB repositories. And you can read the documentation, discuss it on the mailing list, get the source code from Launchpad, and file bug reports on Launchpad.
PS: in addition to Percona Toolkit’s release today, there is also a version 1.0 GA release of the Percona Monitoring Plugins project. It features a variety of bug fixes.