CPU% increases up to 80% after 1 week uptime with insignificant load

Hi,

We are experiencing problems with our Percona Server. After 1 week of uptime the CPU% increases up to 80% with insignificant load. After restarting the server, CPU% drop to less then 3%. This obviously worries us because we expect big growth in the upcoming days. Slowqueries.log does not show us anything significant.

How can we debug this problem?

These are our specs:
Opsys: CentOS release 6.2 (Final)
Kernel: 2.6.32-220.13.1.el6.x86_64 GNU/Linux
Server version: 5.5.27-28.0-log Percona Server (GPL), Release rel28.0, Revision 291

Thank you,
Andrej

Please, are there any suggestions? Why does Percona spend 80% CPU under insignificant load? “Show processlist” shows only 3 or 4 queries that are handled in split millisecond. “Slow queries” does not show anything (even with a threshold value of 0.3 seconds).

Why does Percona spend 80% CPU and after restart less than 3%? I am new to Percona (shifted from MySQL) and most /etc/my.cnf settings are reasonable, as far as I can see.

Should we upgrade version? Or downgrade? Anybody?

See attachement…

Do you have trending graphs for memory usage and disk read/writes from before and after the migration to Percona? I’d be curious to see what is going on there, as if you are swapping or have increased disk access it could be causing the increase in CPU load.

And to clarify, when you say you restarted the server, do you mean just MySQL (Percona), or the entire server?