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Date: Tue, 25 May 2004 02:29:41 -0700
From: Andrew Morton <akpm@osdl.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Help understanding slow down
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Ingo Molnar <mingo@elte.hu> wrote:
>
>  with the patch below we will print a big fat warning. (I did not want to
>  deny idle=poll altogether - future HT implementations might work fine
>  with polling idle.)

idle=poll is handy when profiling the kernel with oprofile clock-unhalted
events.  Because if you use the normal halt-based idle loop no profile
"ticks" are accounted to idle time at all and the results are really hard
to understand.