I upgraded my MySQL server from 5.1 to 5.5 on CentOS (with 2 cores and 2GB RAM).
With my old my.cnf
the mysql service doesn't start anymore (complains about a PID file), so I use an almost empty my.cnf
now.
Now I get iowait
warnings all the time.
This happens even when only trying the application with 1 user.
Anybody has any tips why this happens?
The innodb database is about 500 MB in total, and uses quite large temporary tables in some stored procedures.
I'm searching for the optimal settings of my.cnf
, since I suspect that I should change some default values, but which ones...?