[c-nsp] 3550 High CPU - nothing in proc cpu

[Hector Herrera]

During a high network usage event, the cpu load increased to 90%
sustained, while a 'show processes cpu' did not reveal any culprits.
I suspected IP Input may be consuming a high amount of cpu, but it was
only at 2.7%

The 3550 is working as a L3 router with two static entries for the
default gw (for load balancing on our uplink).

Traffic levels at the time of the high cpu usage were ~120Mbps.

I also examined broadcast packet counts and traffic destined for the
router itself.  They also did not reveal anything out of the ordinary.

Do you have any suggestions on what I should be looking at to
determine the source of the high cpu usage?

Thank you,

Hector