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From: Lee Revell <rlrevell@joe-job.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: Softirq preemption
Date: Tue, 06 Dec 2005 20:31:48 -0500	[thread overview]
Message-ID: <1133919109.15592.22.camel@mindpipe> (raw)
In-Reply-To: <1133464131.7898.30.camel@mindpipe>

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On Thu, 2005-12-01 at 14:08 -0500, Lee Revell wrote:
> Ingo,
> 
> Is there any chance that the softirq preemption feature from the -rt
> kernel can be pushed upstream?
> 

FWIW, here is the longest latency I see with 2.6.14-rt22, with the same
preemption settings as 2.6.14 + PREEMPT.  AFAICT a longish network
softirq gets interrupted by several disk and network interrupts which
adds up to ~1ms.  Is there any easy way to break up this code path that
could be acceptable for mainline, or does this seem like a reasonable
lower limit on achievable latency (until/unless PREEMPT_RT gets merged
etc)?

Lee

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  reply	other threads:[~2005-12-07  1:31 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-12-01 19:08 Softirq preemption Lee Revell
2005-12-07  1:31 ` Lee Revell [this message]
2005-12-07  9:02 ` Ingo Molnar

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