Message-ID: <47D18D9B.9080907@tmr.com>
Date: Fri, 07 Mar 2008 13:46:51 -0500
From: Bill Davidsen <davidsen@tmr.com>
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To: Matthew Hodgson <matthew@mxtelecom.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: Toggling preemption on a running kernel
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Matthew Hodgson wrote:
> Hi,
> 
> I'm trying to compare the performance of some networking code 
> (throughput and latency when receiving various volumes of UDP streams) 
> between a preemptible and non-preemptible 2.6.24 kernel, and was 
> wondering if it is possible to temporarily disable preemption on a 
> running preemptible kernel.  Is it just a matter of loading a module 
> which calls preempt_enable() at load and preempt_disable() at unload - 
> or is that too naive?  Is there an existing way of doing this?
> 
That wouldn't get rid of all the code to support preempt, so it wouldn't 
be useful for comparing much of anything. I think you need to build two 
identical kernels here, with only one difference.

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot
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