Sunday, October 28, 2012

First meeting for MySQL User Group NL announced

Kinderdijk windmills 

With almost 40 member the MySQL User Group NL is already a success.

I've now scheduled the first meeting. It will be on Friday November 16th in Amsterdam. Please signup using the page.

Agenda (See for latest updates)
18:00 Welcome
18:30 First presentation
19:30 Food
20:00 Second presentation

I'm looking for speakers, so feel free to suggest a speaker or to volunteer to speak.

More resources for this user group:

Saturday, October 20, 2012

MySQL AutoTuner

After reading a blog post about MySQL Tuning scripts I thought about the possibility of a fully Automatic MySQL Tuner.

This is how it would work:
A daemon which would connect to your database server and then fetch status variables, just like mysqltuner and such. Then the daemon could decide that a parameter would need to be adjusted and then run "SET GLOBAL …" and write a /etc/mysql/ file which should be included in your my.cnf.

It should have a min/max setting for each option and some thresholds.

  • Not everyone is a DBA
  • It's could better than the default settings is most cases. Luckily many defaults are updated in 5.6.
  • You're not using, are you?
  • It could help when there are changing workloads
  • It might be sufficient for a developer environment
  • MySQL might be embedded in a 'virtual appliance' which can be deployed on may different kinds of hardware.
Why not?
  • The risk of it taking a wrong decision is too high
  • It might be better then the defaults, but still worse than a trained DBA
  • A few important settings (InnoDB Buffer Pool Size and InnoDB Logs) require a restart. I don't like anything to restart MySQL automatically (does your puppet config do automatic restarts?)
  • It might generates differences between servers with the same role. This might not be an issue when the autotuner would use P2P/multicast to communicate with other autotuners, but that makes it even more scary
  • I don't like bolted-on solutions
The conclusion is that I don't think this is a good solution.