Policy Routing - Performance Loss?

[mlsommer]

What kind of performance hit will I see on a Cat6506 running in pure IOS mode when I am exchanging full BGP routes with 2 ISPs and have policy routing enabled? Basically, what I'm interested in is will I have less latency by getting rid of the policy routing altogether and simply load-balancing between the two ISPs to which I'm dual homed? I understand that by utilizing policy routing, CEF & DCEF are not able to be used. With this in mind I assume that latency will likely increase. Is this true? and to what extent?

I would be extremely greatful to anyone who can offer me a little insight and/or a link to some thorough documentation or whitepapers on this.

Thanks,

Matt

[warren]

Unfortunatly there is no "easy" answer to your question. It depends on many things, such as how much traffic is being policy routed. As you stated, policy routed traffic in not CEF switched and so there is a noticible performance hit. From your post it is not clear what you are policy routing... My suggestion is if you do not need to policy-route, don't. It makes configurations more complex and debugging much harder.

What I would suggest is turning off the policy routing and seeing how the latency (and CPU utilization!) changes.