I have run a DS-3 with T-1 backup and an ethernet at near full capacity on a 3640 with no noted performance problems. The CPU load was about 35%. It has been my experience that the CPU load seems to be affected more by the number of running protocols and the number of access lists than traffic forwarding. Once the routing tables are stable and lines are up, the CPU load does not get affected too much by changes in traffic unless there is alot of access list processing. Another point is to find out what the backplane speed limits are because I think your problem running 800Mbps on the 3640 is not a processor constraint but a backplane bandwidth constraint. Cisco shows the capacity at 70,000 packets per second. To give you an idea of how much power this is, one of my 7500 routers is running an OC-3 at about 48 mbps and it shows me that is equal to about 12,000 packets per second. If I extrapolate these numbers I come up with roughly 280 mbps as the rough capacity of the 3640 platform. My traffic is service provider transit so it should be a good mix of packet sizes. I would have to say that the 3640 will handle a fully loaded DS-3 and a fully loaded ethernet connection. Every Cisco I have worked with will be more hurt processor-wise by overly long access lists and flapping protocols more than bandwidth. Steve
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Donn Lasher Sent: Wednesday, February 27, 2002 11:33 AM To: nanog@merit.edu Subject: Line Rate vs CPU utilization info requested
Does anyone have a table / web site / etc that talks about realized IP throughput on various routers (3600 / 7100 / 7200, 5500, 6500, etc) versus cpu load? IE even though you can put 4 x 100M ethernet cards in a 3640, IMHO, you'd never see 400/800M aggregate throughput because the CPU would be on its' knees begging long before that point.
I'm looking at a project that calls for a DS3, and the suggested router is a 3640, and I'm trying to prove / document that's not a wise idea. What has your experience been? Anecdotal or personal experience appreciated. Offline replies work just as well.
Thanks in advance.
-donn