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Date: Tue, 4 Jul 2006 15:51:23 +0200
From: "Christian MICHON" <christian.michon@gmail.com>
Subject: Re: [Qemu-devel] QCow v2
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To: estama@dblab.ece.ntua.gr, qemu-devel@nongnu.org

for what it's worth:
qcow with "lzo -9" would become 4155352 bytes (bigger than original
zlib qcow).

yet it's true at the compression and decompression stages that it
feels faster...

On 7/4/06, Elefterios Stamatogiannakis <estama@dblab.ece.ntua.gr> wrote:
> I agree
>
> Lzma and zlib are pretty much equivalent, so there is pretty much
> nothing to be gained except slightly more compression.
>
> On the other hand with lzo (1) there would be quite a considerable speed
> improvement at the cost of compression.
>
> It could also mean that reading on the qcow format could some times be
> faster (with compressible data) than   reading directly from the hard disk.
>
> lefteris
>
> (1) http://www.oberhumer.com/opensource/lzo/
>
> Johannes Schindelin wrote:
> > Hi,
> >
> > On Tue, 4 Jul 2006, Christian MICHON wrote:
> >
> >> how about also adding lzma compression for qcow ?
> >
> > Why lzma? We already have a dependency on zlib, why not just take that?
> >
> > Ciao,
> > Dscho
> >
> >
> > _______________________________________________
> > Qemu-devel mailing list
> > Qemu-devel@nongnu.org
> > http://lists.nongnu.org/mailman/listinfo/qemu-devel
>
>
> _______________________________________________
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>


-- 
Christian