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Date: Tue, 9 Oct 2012 19:32:16 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Steven Rostedt <rostedt@goodmis.org>
cc: LKML <linux-kernel@vger.kernel.org>,
        linux-rt-users <linux-rt-users@vger.kernel.org>,
        Carsten Emde <cbe@osadl.org>
Subject: Re: [ANNOUNCE] 3.6.1-rt1
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On Tue, 9 Oct 2012, Steven Rostedt wrote:
> On Tue, 2012-10-09 at 18:19 +0200, Thomas Gleixner wrote:
> >  
> > > I've started looking at playing with the NAPI code again, and trying to
> > > see if I can add an ENAPI interface (Even Newer API), where the driver
> > > uses its own interrupt thread, and instead of having the polling in the
> > > network softirq, it can do the polling in its own thread.
> > 
> > It's pretty close to the behaviour I enforced with this change. Let's
> > play with that and figure out what influence it has on the network
> > throughput performance on RT. That needs probably a different
> > scheduling scheme than what Carsten needs for his deterministic
> > behaviour.
> > 
> 
> I was actually looking at the change for mainline, not for -rt ;-)

I know, but you can utilize RT for figuring out what kind of
performance impact (in whatever direction) this modus operandi
has. That gives us a better understanding and hopefully improvements
for RT, but at the same time a lot of insight in how we should handle
this scenario on a non RT kernel. You might try to make the softirq
split lock scheme work in CONFIG_RT_BASE as this gives us a way better
comparison to mainline behaviour.

Thanks,

	tglx