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Subject: Re: [PATCH,RFC] faster kmalloc lookup
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Manfred Spraul <manfred@colorfullife.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Sat, 2002-10-26 at 20:22, Manfred Spraul wrote:
> kmalloc spends a large part of the total execution time trying to find 
> the cache for the passed in size.
> 
> What about the attached patch (against 2.5.44-mm5)?
> It uses fls jump over the caches that are definitively too small.

Out of curiousity how does fls compare with finding the right cache by
using a binary tree walk ? A lot of platforms seem to use generic_fls
which has a lot of conditions in it and also a lot of references to just
computed values that look likely to stall 

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