KCO-CORESWITCH-01#sh processes cpu sorted
Core 0: CPU utilization for five seconds: 3%; one minute: 14%; five minutes: 9%
Core 1: CPU utilization for five seconds: 96%; one minute: 88%; five minutes: 87%
PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
-->9816 3044033 18315896 1 50.71289 49.28906 48.27832 0 iosd <--
It appears that your IOS demon is the PID responsible for Chewing up your 2nd core,
A good read would be this document here,
http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a00800a70f2.shtml
Regards Neil
http://uk.linkedin.com/pub/neil-grant/20/5b0/267