For some reason, all my mysql servers have gone to 100% cpu usage in the last few hours. Stopping NTPd and mysql (at least on those servers that are on kvm/xen) and running
date -s "`date`"
Seems to have fixed it. It has not only affected kvm/xen VPSes, but also two of my OVZ VPSes as well (which ive shut mysql down on and am waiting for a response from the host).
Did something go crazy with the ntp servers or something?
Side Note: I am running percona server 5.6, so this may be a bug in this specific variant.