qcow2 compression [was Re: F20 System Wide Change: Visible Cloud]

[Richard W.M. Jones]

On Mon, Jul 15, 2013 at 07:14:04PM +0100, Richard W.M. Jones wrote:
> On Mon, Jul 15, 2013 at 01:36:57PM -0400, Matthew Miller wrote:
> > Seekable xz/lzma compression instead of zlib/deflate.
> 
> In qcow2, each [by default] 64K cluster is compressed independently.

... and I should say there's a 2-level tree at the start of the file
which maps every cluster to a file offset, which is why ...

> seeking is great,

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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