Freebsd IP Forwarding performance (question, and some info) [7-stable, current, em, smp]

[Paul]

I tested Linux in bridge configuration with the same machine and it 
CPUed out at about 600kpps through the bridge..
That's a bit low :/   Soft interrupt using all the cpu.  
Same opteron 2222, 82571EB Pci express NIC.
Tried SMP/ non-smp , load balanced irqs, etc..

Good news is using iptables only adds a few percentage onto the CPU 
usage.   But still, what's with that..
So far FreeBSD got the highest pps rating for forwarding. I  haven't 
tried bridge mode.  Ipfw probably takes a big hit in that too though.

Looking for an 82575 to test..


Paul