[virt-tools-list] sparse files and ls

[Richard W.M. Jones]

On Wed, Jun 15, 2011 at 02:00:36PM +0100, Paul Mansfield wrote:
> On 14/06/11 13:02, Richard W.M. Jones wrote:
> > qcow2 uses a two-level directory.  The second level is not allocated
> > until required unless you selected the "preallocation" option when
> > creating the disk.  So if you didn't use "-o preallocation" then yes
> > this overhead can grow as more disk blocks get allocated.  By the way,
> > we found that preallocation is faster.
> > 
> > Mark wrote extensive documentation on qcow2 here:
> > 
> > http://people.gnome.org/~markmc/qcow-image-format.html
> 
> that's very helpful, thanks

BTW there's also preallocation=metadata option which preallocates
just the directory.

Rich.

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