Red Hat Bugzilla – Full Text Bug Listing
|Summary:||RFE: More info in qemu-img info|
|Product:||[Fedora] Fedora||Reporter:||Alexander Larsson <alexl>|
|Component:||qemu||Assignee:||Fedora Virtualization Maintainers <virt-maint>|
|Status:||CLOSED UPSTREAM||QA Contact:||Fedora Extras Quality Assurance <extras-qa>|
|Version:||18||CC:||amit.shah, berrange, cfergeau, crobinso, dwmw2, itamar, knoel, kwolf, pbonzini, rjones, scottt.tw, stefanha, virt-maint|
|Fixed In Version:||Doc Type:||Bug Fix|
|Doc Text:||Story Points:||---|
|:||861439 920225 (view as bug list)||Environment:|
|Last Closed:||2012-12-14 20:25:36 EST||Type:||Bug|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
|Bug Depends On:|
|Bug Blocks:||861439, 920225|
Description Alexander Larsson 2012-09-28 08:07:45 EDT
qemu-img info currently give me info like this: image: /home/alex/.local/share/gnome-boxes/images/Fedora 16 file format: qcow2 virtual size: 11G (11794287616 bytes) disk size: 4.5G cluster_size: 65536 In order to figure out the "health" of an image there is some more information I would like: in-use disk size - I.e the subset of disk size that is not marked as unused due to e.g. TRIM operations amount of compressed clusters. I.e. "is it useful to re-compress the image". Fragmentation estimation. This would be useful to both sysadmins in general and for automated things like what we want to do in gnome-boxes: https://bugzilla.gnome.org/show_bug.cgi?id=685032
Comment 1 Richard W.M. Jones 2012-09-28 08:18:50 EDT
All sounds useful. However these requests should probably go upstream, along with patches! Note upstream there is a patch floating around which adds JSON output to qemu-img info. This is useful because it's a big security problem to try to parse the text output from this command. See: https://lists.gnu.org/archive/html/qemu-devel/2012-09/msg00137.html
Comment 2 Daniel Berrange 2012-09-28 11:38:08 EDT
Depending on how Boxes wants to consume this extra metadata, this may need to be done in libvirt instead, or as well. Libvirt does not actually use qemu-img info for getting file metadata, since it wants a low overhead code to extra basic properties & forking qemu-img doesn't really satisfy that.
Comment 3 Paolo Bonzini 2012-09-28 11:39:31 EDT
Fragmentation estimation and in-use space is actually quite expensive to compute---not *that* expensive but certainly worse than a fork, and worse-case O(n) in the size of the disk.
Comment 4 Stefan Hajnoczi 2012-10-23 06:17:08 EDT
Fragmentation statistics have been added to 'qemu-img check' for qcow2 and qed image files: commit f8111c241afa75544032dcfa23df0699c91f9866 Author: Dong Xu Wang <email@example.com> Date: Thu Mar 15 20:13:31 2012 +0800 qemu-img: add image fragmentation statistics Note this is qemu-img check and not qemu-img info, because we need to scan the image metadata (expensive on large images).
Comment 5 Kevin Wolf 2012-10-23 07:58:28 EDT
Yes, I agree that most of this should be part of 'qemu-img check' rather than 'qemu-img info'. Fragmentation statistics are only implemented for QED as of today, qcow2 doesn't have them yet.
Comment 6 Cole Robinson 2012-12-14 20:25:36 EST
In general I don't think RFE's make much sense in Fedora bugzilla, so I've moved this to the upstream qemu tracker: https://bugs.launchpad.net/qemu/+bug/1090615 Alex, I couldn't find a launchpad account for you, but please follow up on that report (or qemu-devel)