On Fri, May 18, 2012 at 12:13 AM, Eric Blake <ebl...@redhat.com> wrote: > Meta-question - is pre-allocation something that is persistent with the > existence of the storage volume, or is it something that is one-shot at > the creation of the volume?
>From what I gather, there doesn't seem to be any flag telling you if the qcow2 was preallocated, although I guess there should be a way to somehow guess that. I think I understand your point, and you may be right that a flag at creation time might be better. But, the fact that we can't easily know from the img itself if it was preallocated is also a loss of information. For example, if a user-friendly client wanted to warn the user of potential slowness due to a qcow2 image created without preallocation, it would be nice to keep that information somewhere, or perhaps implement that "guessing" at the "qemu-img info" level. But if we go that way, then why don't we query the image for all the data it has instead of storing them in the XML, such as capacity? Isn't allocation also a creation-time only value? -- Marc-André Lureau -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
