Ghetto Profiling for MySQL

Posted by chetan on July 29, 2008 in mysql, software

MySQL is generally an all-around kickass piece of software, and like any good open source application, there are a host of tools you can use to squeeze every last drop of goodness out of it. Nearly all of them, however, are geared towards the operational DBA, leaving the wayward developer out in the cold.

Lately I’ve been working on optimizing our stored procedure library which is primarily responsible for generating all sorts of fancy reports for the users. We use lots of nested procedure calls and finding potential targets for optimization is a tricky and time consuming job. Enter Ghetto Profile.

It’s still pretty basic but gets the job done. How’s it work?

ghetto_profile.rb --attach crappy_code.sql
mysql < crappy_code.sql
ghetto_profile.rb --stats -uroot -pmysql

The attach command simply wraps all stored procedure calls with debug statements which can later be analyzed using the stats command.

CALL debug.on('stored_proc1'); -- added by ghetto_profile
    CALL stored_proc1(...params...);
CALL'stored_proc1'); -- added by ghetto_profile

And the output of the stats command is something like this:

total time: 3718.3220
         pct:   75.3873
         total: 2803.1430 (46.72)
         avg:   0.0895
         count: 31327
         min:   0.0860000000000001
         max:   0.343
         pct:   22.9479
         total: 853.2760 (14.22)
         avg:   0.0273
         count: 31240
         min:   0.0
         max:   0.371
         pct:   1.1224
         total: 41.7340 (0.70)
         avg:   0.0007
         count: 59020
         min:   0.0
         max:   0.074

Wow, that stored_proc1 is taking up 75% of the time! Hacking ensues…

total time: 1151.3400
         pct:   0.4372
         total: 5.0340 (0.08)
         avg:   0.0001
         count: 43892
         min:   0.0
         max:   0.007

Totally sweet! Ok, enough talk. Get some:

Ghetto Profile 0.7 (requires ruby, BSD licsensed)
debug.tgz (helper package to setup the debug database and procs)