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Date: Tue, 4 Jul 2006 15:16:24 +0200
From: "Christian MICHON" <christian.michon@gmail.com>
Subject: Re: [Qemu-devel] QCow v2
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To: qemu-devel@nongnu.org

ok, I used "split -b 4k" on a 7716864 bytes qcow.
I used standard lzma compression and get 1884 7z-clusters
with a grand total of 3558617 bytes (indeed the gain is small).

The standard zlib qcow gave 3704180 bytes...

Does it make sense to have a cluster based compression ?
Indeed the actual compression is not so impressive then (zlib
or not zlib based).

On 7/4/06, Christian MICHON <christian.michon@gmail.com> wrote:
> sorry I was not clear here...
>
> On 7/4/06, Fabrice Bellard <fabrice@bellard.org> wrote:
> > > how to split into individual clusters a qcow image ?
> >
> > A good approximation is to use an uncompressed qcow image, or even a raw
> > image in which you exclude the empty clusters.
> >
> > Fabrice.
>
> how do I cut into the actual 4k clusters an existing qcow image ?
> any bash script or executable to perform this trick ?
>
> --
> Christian
>


-- 
Christian