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Date: Tue, 22 Nov 2011 18:23:44 +0100
From: Matthieu CASTET <matthieu.castet@parrot.com>
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To: Mark Brown <broonie@opensource.wolfsonmicro.com>
Subject: Re: [PATCH 1/3] Add the snappy-c compressor to lib
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Cc: Mike Dunn <mikedunn@newsguy.com>,
 "linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>,
 Artem Bityutskiy <dedekind1@gmail.com>
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Mark Brown a écrit :
> On Thu, Nov 17, 2011 at 11:36:17PM +0200, Artem Bityutskiy wrote:
> 
>> Yeah, of course it would be interesting to see. If snappy is a win-win
>> on ARM, we should merge it.
> 
> It might be interesting to use it for the compressed cache type in regmap
> as well.
> 
For info we did some bench mark on omap3 (cortexa-8) for decompressing
hibernation image.
And snappy was a lose-lose against lzf (bigger compressed result, slower to
decompress) :

algo : compressed size , time to decompress
snappy (16 and 32 bits unaligned access done by hardware) : 45Mo, 3.5 s
snappy (unaligned access done by software) : 45Mo, 2.50 s
lzf (unalign access done by softare) : 40Mo, 2.35 s


Of course this is against one pattern (hibernation image) and benchmark should
be done on other patterns.

Matthieu