Hi,

I am using a machine with only a 500Mhz VIA cpu as NAT/IPSEC gateway  
here at the har2009.org camp.
Sometimes the internet is hardly usable, loadavg spikes up to  14.  
When investigating I see 80-90% of the CPU time is because of interupts.
Almost all interrupts  are for the rl0 and rl1 interface.

The interrupt load is not coupled to bandwith usage, we can use 60Mbit  
without any problems.
I know rl(4) cards are crappy but I am wondering what could cause  
these strange spikes?
It must be because of packets per second, but I can't find a offender.  
Are there any tweaks to mitigate the effects?

Right after the load spikes (normally these last for 15 minutes) the  
IPSEC tunnels are not in a usable state anymore.
Does anyone have a workaround for this?

Kind regards,
Wijnand