question about softirqs

[Steven Rostedt]

On Tue, 12 May 2009, Peter Zijlstra wrote:

> On Tue, 2009-05-12 at 11:23 +0200, Ingo Molnar wrote:
> > 
> > Yeah, that would be "nice". A single IRQ thread plus the process 
> > context(s) doing networking might perform well.
> > 
> > Multiple IRQ threads (softirq and hardirq threads mixed) i'm not so 
> > sure about - it's extra context-switching cost.
> 
> Sure, that was implied by the getting rid of softirqs ;-), on -rt we
> currently suffer this hardirq/softirq thread ping-pong, it sucks.

I'm going to be playing around with bypassing the net-rx/tx with my 
network drivers. I'm going to add threaded irqs for my network cards and 
have the driver threads do the work to get through the tcp/ip stack.

I'll still keep the softirqs for other cards, but I want to see how fast 
it speeds things up if I have the driver thread do it.

-- Steve