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Date: Mon, 2 Apr 2007 09:21:11 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Dave Sperry <dave_sperry@ieee.org>
Cc: linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Poor UDP performance using 2.6.21-rc5-rt5
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* Dave Sperry <dave_sperry@ieee.org> wrote:

> I have a dual core Opteron machine that exhibits poor UDP performance 
> (RT consumes more than 2X cpu) with the 2.6.21-rc5-rt5 as compared to 
> 2.6.21-rc5. Top shows the IRQ handler consuming a lot of CPU.

update: even with acpi_pm clocksource on vanilla i can reproduce similar 
overhead using netperf.

	Ingo