openvpn performance on WRAP

I am seeing about 300-400Kbytes/sec
(so up to 4Mbps) on openvpn - as measured, no compression, using scp from/to
big machines on either end of the VPN.

The WRAPs seem to do 15-20MBit/sec OK
raw TCP - as measured between the same servers, but using scp 'in the clear'
over the internet.

when openvpn tops out, the CPU isnt
maxed out at all. I haven enabled polling, and kernel polling:
kern.polling.enable=1
kern.polling.user_frac=90  (tried
a few values between 50 and 90)

The polling keeps down the %cpu used
by interrupts. I think the slowness is some other timing issue or something.

I have also tried WRAP to vmware with
P4 2ghz (not the fastest, but available at the time) - same throughput,
much less CPU usage.

as an aside I seem to have to reload
firewall rules everytime I restart, as the vpn gets packets blocked, eevn
thought the rules allow the packets, after restarting the firewall its
all good.

Scott
sfarrell@xxxxxxxxxxxxxxxxxxx