I have Percona Server 5.5.24 on a Centos 6 server, installed from percona yum repository, and I noticed that suddenly mysqld started consuming 100% CPU.
There is nothing shown in the processlist, in fact, this issue remains even if I disconnect database from all client applications.
I set up a slave on another server for backups, and it is affected with the same issue.
Also I noticed a high number of timer0 and timer1 interrupts that coincide with cpu load increase. Graph is attached.