Re: [Qemu-devel] [RFC] qed: Add QEMU Enhanced Disk format

[Anthony Liguori]

On 09/08/2010 03:23 PM, Christoph Hellwig wrote:
> On Wed, Sep 08, 2010 at 11:30:10AM -0500, Anthony Liguori wrote:
>    
> > http://wiki.qemu.org/Features/QED/OnlineDefrag
> >
> > Is a spec for a very simple approach to online defrag that I hope we can
> > implement in the near future.  I think that once we have the mechanisms
> > to freeze clusters and to swap clusters, implementing much more
> > sophisticated defragmentation algorithms will become easy.
> >      
> This image defragmentation might in fact cause even more fragmentation
> at the filesystem layer.
>    

That's a good point.  Is there a reasonable way to do this cooperatively 
with the underlying filesystem?

BTW, the same problem would occur for sparse file system images, no?

Regards,

Anthony Liguori