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Date: Fri, 12 Jan 2007 09:59:40 +0000
From: Alan <alan@lxorguk.ukuu.org.uk>
To: Nick Piggin <npiggin@suse.de>
Cc: Andrew Morton <akpm@osdl.org>, Ingo Molnar <mingo@elte.hu>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [patch] sched: avoid div in rebalance_tick
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On Fri, 12 Jan 2007 07:02:13 +0100
Nick Piggin <npiggin@suse.de> wrote:

> Just noticed this while looking at a bug.
> Avoid an expensive integer divide 3 times per CPU per tick.

Integer divide is cheap on some modern processors, and multibit shift
isn't on all embedded ones.

How about putting back scale = 1 and using

scale += scale;

instead of the shift and getting what ought to be even better results