On Tue, Oct 26, 2010 at 02:11:22AM +1100, Justin Clift wrote: > On 10/26/2010 01:06 AM, Richard W.M. Jones wrote: > <snip> > >> 4. A metadata preallocated qcow2 file: 14.5 seconds > >> qemu-img create -f qcow2 -o preallocated=metadata test.img 300M > > Just tested this on a F13 host, and it didn't like the the preallocated > option: > > $ qemu-img create -f qcow2 -o preallocated=metadata testvm.qcow2 20G > Unknown option 'preallocated' > qemu-img: Invalid options for file format 'qcow2'. > $ > > Looks like we'd need to add some kind of testing for the capability > first. :) The option should be '-o preallocation=metadata'. This works for me on Fedora 13 too. This option was introduced to qemu upstream in commit a35e1c177debb01240243bd656caca302410d38c (Aug 17 2009). You could actually detect this at runtime by running: $ qemu-img create -f qcow2 -o preallocation=metadata /dev/null 1M Formatting '/dev/null', fmt=qcow2 size=1048576 encryption=off cluster_size=0 preallocation='metadata' $ echo $? 0 $ qemu-img create -f qcow2 -o preallocation=foobar /dev/null 1M Formatting '/dev/null', fmt=qcow2 size=1048576 encryption=off cluster_size=0 preallocation='foobar' Invalid preallocation mode: 'foobar' qemu-img: Error while formatting $ echo $? 1 However the first command segfaults on Fedora 14 (so near and yet so far!) I'm going to file a bug about that. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming blog: http://rwmj.wordpress.com Fedora now supports 80 OCaml packages (the OPEN alternative to F#) http://cocan.org/getting_started_with_ocaml_on_red_hat_and_fedora -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list