Had a partner doing backups acoss the network between a 3750 and 6513 core switch ove a gigabit backbone. it looks like this caused issues with other connections through the 6513. It looks like the gigabit port was going up to 10MB which does not seem that high. I would see time outs on pings when we stopped the backups it looks like the problem may have gone away. i have been looking for commands to use on the 6513 to see utilzation for the cpu and ports to troubleshoot this.
1.For CPu utilization
"show process cpu | exclude 0.00"
2.For interface regular commands like
"show interface ***"
Look for load,input rate,output rate
Clear the counters , before starting monitoring the interface.
3.Other option is Netflow
HTH..rate if helpful..
show proc - will give you cpu util for :-
5 seconds - 1 minute - 5 minutes
sh int gig x/x accounting
sh int gig x/x counters
show int gig x/x
All will give good stats etc.