Sign up ×
Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. It's 100% free, no registration required.

MySQL is eating up about 80% of my CPU for no reason as far as I can see. Right now this server is rarely used, more of a test site I set up that will eventually be a used for production once I fix small problems like this. I run 3 instances of MySQL but it seems that my first instance is taking up all the CPU. When I turn off the first instance and leave the other two on everything runs fine.

Any suggestions?

I tried Show Processlist and no statements are being run besides "Sleep" and the query "Show Processlist" (obviously) at the time it's using up all this CPU.

my.cnf is basic. I did not optimize or change any MySQL settings. Do you think this would cause such strange behavior?

The machine is running Linux Centos 5.7 64 bit and MySQL 5.0.95.


share|improve this question
Try "ps -eLf | grep -i mysql | less -S" to see which thread is the one using the CPU – golimar Feb 28 '12 at 14:29
I type that command and a bunch of lines show up, what exactly am I looking for? – Robert Feb 28 '12 at 14:48
In column 5 check for a high value, that's the thread you want; column 4 is its LWP or thread id – golimar Feb 28 '12 at 15:01
ok its the first instance it has a value of "76". – Robert Feb 28 '12 at 15:47
try to get information about the thread, in the /proc/<LWP> directory – golimar Feb 28 '12 at 16:57

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.