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Subject: Re: [patch] voluntary-preempt-2.6.8.1-P4
From: Lee Revell <rlrevell@joe-job.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
       Thomas Charbonnel <thomas@undata.org>,
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       Felipe Alfaro Solana <felipe_alfaro@linuxmail.org>
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On Fri, 2004-08-20 at 06:27, Ingo Molnar wrote:
> * Lee Revell <rlrevell@joe-job.com> wrote:
> 
> > This is an extreme load situation, so I don't think it will be a
> > real-world problem.  I have not seen it under any normal workload.
> 
> well, 9 msecs is still not nice. I've been able to trigger larger than
> 10msec latencies too on a 2 GHz box.
> 

If this is the case then should a make -j12 have ground the machine 
to a halt the way it did?

> hm, tcp_collapse() in net/ipv4/tcp_input.c. Could you try to just return
> from that function?  Collapsing skbs of a given socket is not a
> necessary functionality (it is only a 'nice' thing to have in OOM
> situations) and it indeed can introduce quite high latencies.
> 

OK, will test this.

Lee