On Fri, Aug 20, 2010 at 11:33:02AM +0800, Kirby Zhou wrote:
 Does the appliance support ext4/reiserfs/btrfs now? 
Yes, for a long time:
http://rwmj.wordpress.com/2009/11/08/filesystem-metadata-overhead/
Rich.
-- 
Richard Jones, Virtualization Group, Red Hat 
http://people.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://et.redhat.com/~rjones/virt-df/