Heli from Oracle User Group Finland invited me to speak at this years OUGF Harmony conference which starts tomorrow. Last year I had some proposals accepted but had to decline due to work travel.

This year they wanted to learn more about Galera and I was of course more than happy to go and speak. My talk is titled "Synchronous Multi-Master Clusters with MySQL: an Introduction to Galera." It contains some parts of what we presented at the MySQL Conference, but is more of an introduction and less about benchmarking.

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OpenStack comprises of many projects, all of which have code reviews via. Gerrit and every code review is tested with many tests on Jenkins.  Whilst this is excellent for code quality this can get quite insane to manage.  In fact at time of writing OpenStack's Jenkins server now has a shade under 300 jobs to manage, I don't know about you but I really don't want to be spending my days managing all of that.  Often we need to make a small change to many jobs at the same time and human error occurs.  In the last few weeks we developed and unveiled the CI team's solution to this: Jenkins Job Filler (aka. Jenkins Job Builder when I forget what we called it).

The initial version of Jenkins Job Filler was written in a combination of Ruby and Puppet scripts but unfortunately it became unmanageable very quickly, it also required a Jenkins restart on every change.  So the new version has been writing in Python and YAML. …

Following the release of MySQL Cluster 7.2, the Engineering has been busy publishing a range of new performance benchmarks, most recently delivering 1.2 Billion UPDATE operations per Minute across a cluster of 30 x commodity Intel Xeon E5-based servers.

Figure 1: Linear Scaling of Write Operations

These performance tests have been run on the flexAsynch benchmark, so in the this blog, I wanted to provide a little more detail on that benchmark, and provide guidance on how you can use it in your own performance evaluations.

FlexAsynch is an open source, highly adaptable test suite that can be downloaded as part of the MySQL Cluster source tarball under the <storage/ndb/test/ndbapi> directory.

An …

In MySQL cluster each SQL statement is translated inside the NDB storage engine to NDB low level protocol that is sent to the data nodes. For the performance it is most interesting how many data is moved between data nodes and MySQL. To monitor this there are several NDB status variables that you can monitor. See this link for more documentation.

(There are also the NDBINFO tables that reflect cluster status. But these are only global values. The status variables also show session status. More about NDBINFO is here.)

To easily report the NDB status on an individual SQL statement, I wrote a little script that gives you the ndb status variables and automatically calculates the diffs before and after the statement in …

I finally got around to cleaning up old contact me messages. One of the messages raises a question about RESULT_CACHE functions. The writer wanted an example implementing both a standalone schema and package RESULT_CACHE function.

The question references a note from the Oracle Database 11g PL/SQL Programming book (on page 322). More or less, that note points out that at the time of writing a RESULT_CACHE function worked as a standalone function but failed inside a package. When you tried it, you raised the following error message:

PLS-00999: Implementation Restriction (may be temporary)

It’s no longer true in Oracle 11gR2, but it was true in Oracle 11gR1. I actually mentioned in a …

The UK Oracle User Group Conference is the UK's largest independent Oracle Technology & E-Business Suite conference. It takes place December 3-5 2012 in Birmingham.

The call for papers is running until Friday June 1st and MySQL sessions are welcome. You can submit them here.

After reading www.postgresq.org now active over IPV6 by default I quickly tried some other host to see what the current state of IPv6 is for some known database websites.

$ getent hosts mysql.com percona.com askmonty.org postgresql.org oracle.com sqlite.org code.openark.org skysql.com drizzle.org
156.151.63.6    mysql.com
74.121.199.234  percona.com
173.203.202.13  askmonty.org
2a02:16a8:dc51::50 postgresql.org
137.254.16.101  oracle.com
67.18.92.124    sqlite.org
69.89.31.240    code.openark.org
94.143.114.49   skysql.com173.203.110.72  drizzle.org



So only postgresql.org supports IPv6 right now. On the MySQL side Facebook is one of the known IPv6 …

1. Percona Toolkit
Percona Toolkit (aka Maatkit and Aspersa) is must have collection of advanced command-line tools which helps in performing tasks that are too difficult or complex to perform manually.

2. Mydumper
Mydumper is a high-performance multi-threaded backup/restore tool for MySQL. It’s up to 10x faster compared to mysqldump, can take consistent snapshots and provides File compression on-the-fly. Though it’s still under active development but is well tested/used in production on some large installations.

3. MySQL Master HA
This tool helps to maintain your Master-Slave replication setup. A primary objective is automating master fail-over and slave …

We’re quite happy that we’ve released four major releases that are production ready (better known as generally available or GA in the MySQL world) in the last 26 months. That is just a little over two years, and a whole lot of features. In that same time, MySQL has seen one GA release (MySQL 5.5) and we’re all eagerly awaiting the upcoming MySQL 5.6.

You’ll note that we built MariaDB 5.1, 5.2, and 5.3 based on the MySQL 5.1 codebase. A significant number of features went into MariaDB 5.3 (our biggest GA release to date), with the biggest changes in the optimizer in over a decade. There were also many replication based …

There was a point a few years ago where Sun could have had the next generation UNIX filesystem. It was in Solaris (and people were excited), there was a port to MacOS X (that was quite exciting for people) and there was a couple of ways to run it on linux (and people were excited). So… instead of the fractured landscape of ext3, HFS+ and (the various variations of) UFS we could have had one file system that was common between all of the commonly used UNIX-like variants. Think of being able to use a file system on a removable drive that isn’t FAT and being able to take it from machine to machine (well… Windows would be a problem, but it always is).

There was some really great work done in OpenSolaris with integration between the file manager and ZFS snapshots (a slider bar to browse the history of a directory, an idea I’ve championed for over a decade now, although the Sun implementation was likely completely independently developed). …