From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: Poor UDP performance using 2.6.21-rc5-rt5
Date: Mon, 2 Apr 2007 07:55:09 +0200
Message-ID: <20070402055509.GC3284@elte.hu>
References: <461004CE.1030009@ieee.org> <461010F9.7040706@us.ibm.com>
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Cc: Dave Sperry <dave_sperry@ieee.org>, linux-rt-users@vger.kernel.org,
	linux-kernel@vger.kernel.org, netdev <netdev@vger.kernel.org>
To: Nivedita Singhvi <niv@us.ibm.com>
Return-path: <linux-rt-users-owner@vger.kernel.org>
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* Nivedita Singhvi <niv@us.ibm.com> wrote:

> Dave Sperry wrote:
> >Hi
> 
> (adding netdev to cc list)

in general (except of course those netdev folks that are interested in 
-rt+networking performance matters) i'd suggest we analyze this in an 
-rt specific way - netdev shouldnt have to bother about this.

> And I'm assuming nothing very different in the stats or errors through 
> both runs?

one thing to check would be whether both kernels use the same 
clocksource, via:

 cat /sys/devices/system/clocksource/clocksource0/current_clocksource

but at first sight there's no clocksource related overhead in the 
oprofile.

	Ingo