Ever since Peter over at Percona wrote about MySQL and swap, I’ve been meaning to write this post. But after I saw Dathan Pattishall’s post on the subject, I knew I’d better actually do it.

There’s a nasty problem with Linux 2.6 even when you have a ton of RAM. No matter what you do, including setting /proc/sys/vm/swappiness = 0, your OS is going to prefer swapping stuff out rather than freeing up system cache. On a single-use machine, where the application is better at utilizing RAM than the system is, this is incredibly stupid. Our MySQL boxes are a perfect example – they run only MySQL and we want InnoDB to have a lot of RAM (32-64GB …

Day two of the conference was a little disappointing, as far as sessions went. There were several time blocks where I simply wasn’t interested in any of the sessions. Instead, I went to the expo hall and tried to pry straight answers out of sly salespeople. Here’s what I attended.

Paying It Forward: Harnessing the MySQL Contributory Resources

This was a talk focused on how MySQL has made it possible for community members to contribute to MySQL. There was quite a bit of talk about IRC channels, mailing lists, and the like. However, the talk gave short shrift to how MySQL plans to become truly open source (in terms of its development model, not its license). I think there was basically nothing to talk about there. I had a good conversation about some of my concerns with the speaker and some others from MySQL right afterwards.

There was basically nobody there — I didn’t count, but I’d say maybe 10 or 12 people. I …

Today is the first day at the conference (aside from the tutorials, which were yesterday). Here’s what I went to:

New Subquery Optimizations in 6.0

By Sergey Petrunia. This was a similar session to one I went to last year. MySQL has a few cases where subqueries are badly optimized, and this session went into the details of how this is being addressed in MySQL 6.0. There are several new optimization techniques for all types of subqueries, such as inside-out subqueries, materialization, and converting to joins. The optimizations apply to scalar subqueries and subqueries in the FROM clause. Performance results are very good, depending on which data you choose to illustrate. The overall point is that the worst-case subquery nastiness should be resolved. I’m speaking of WHERE NOT IN(SELECT…) and friends. It remains to be seen how this shakes out as 6.0 matures, and what edge cases will pop up.

The Lost Art Of the Self …

Effective April 1, I will join Percona full-time as a consultant. I’ll be helping people build high-performance applications with MySQL, but I’ll also be continuing to develop and improve tools such as Maatkit.

This career change has been a long time in progress. I’m really looking forward to it, but at the same time it’s hard to leave my current employer, The Rimm-Kaufman Group (RKG). Working with them has been the best job I’ve ever had. But ultimately, my dream job is to help as many people as I can, and consulting will be a better way to do that.

At a time like this, I like to reflect on the trail that has led here. It’s a good opportunity to realize how fortunate I really am and fill up my gratitude tank. So I’d like to thank everyone who has …

A lot of people contact me asking if I’m looking for a job. (I have an unanswered email in my inbox right now.) People are looking desperately for qualified, knowledgeable MySQL professionals. There’s a critical shortage of people who can admin MySQL moderately well, much less at the guru level.

If you are one of the many who are trying to hire a MySQL DBA, you should send your employees to the MySQL Conference and Expo. Not just this year — every year. Train a smart person instead of trying to hire someone who’s ready to go now.

This is the unfortunate reality: MySQL’s popularity has caused demand to far exceed supply. That’s what happens when a great disruptive innovation takes hold.

What do you do in the meantime?

If you just need a little help, hire a part-time DBA and get some consulting help. Without endorsing them directly, may I suggest …

A while ago I asked for people and/or organizations to sponsor development on Maatkit (formerly MySQL Toolkit) so I could take a week off work and improve the Table Sync tool. I asked for $2500 USD, but several companies have graciously offered to cover that and then some.

I'm very happy about this, as it will allow me to dedicate a solid week to fixing bugs and adding features. There's a lot of demand for the tools, and there are a dozen or so bug reports unresolved for the table-sync tool, which I personally want to fix as much as anyone. So I'm very grateful for the support.

Here are the companies who have promised their financial support:

MySQL AB

…