On Thu, 23 Jun 2016 17:57:53 +0100 "Richard W.M. Jones" <rjones@redhat.com> wrote:
On Thu, Jun 23, 2016 at 10:57:43AM -0500, libvirt_users@skagitattic.com wrote:
Thanks for all the information, I think my last remaining question is why the image created with virt-install shows the full apparent size and the image from virt-sparsify does not? (The image testimage1.qcow2 created with default options).
I don't really know what you mean by "full apparent size". If you are talking about the output of "ls -l", then don't -- that number is unrelated to the virtual size or the space consumed on disk. Always use "qemu-img info".
So I think I figured out what's different. If I do preallocation=metadata I end up with the apparent size the same as the initial install. # virt-sparsify testimage.qcow2 testimage3.qcow2 --tmp /bigtmp -o preallocation=metadata Input disk virtual size = 53687091200 bytes (50.0G) Create overlay file in /bigtmp to protect source disk ... Examine source disk ... Fill free space in /dev/sda1 with zero ... 100% 00:00 Clearing Linux swap on /dev/sda5 ... Copy to destination and make sparse ... Sparsify operation completed with no errors. Before deleting the old disk, carefully check that the target disk boots and works correctly. # ls -lsh testimage.qcow2 testimage1.qcow2 testimage3.qcow2 1.1G -rw-r--r-- 1 root root 1.1G Jun 22 22:41 testimage1.qcow2 1.1G -rw-r--r-- 1 root root 51G Jun 23 16:20 testimage3.qcow2 2.5G -rw-r--r-- 1 root root 51G Jun 22 20:22 testimage.qcow2 I don't know how to tell what the image's pre-allocated state is other then checking for apparent size as "qemu-img info" does not see a difference (other then the fact I played around with snapshotting on the testimage1). # qemu-img info testimage1.qcow2 image: testimage1.qcow2 file format: qcow2 virtual size: 50G (53687091200 bytes) disk size: 1.1G cluster_size: 65536 Snapshot list: ID TAG VM SIZE DATE VM CLOCK 1 test 0 2016-06-22 22:41:44 00:00:00.000 Format specific information: compat: 1.1 lazy refcounts: false # qemu-img info testimage3.qcow2 image: testimage3.qcow2 file format: qcow2 virtual size: 50G (53687091200 bytes) disk size: 1.0G cluster_size: 65536 Format specific information: compat: 1.1 lazy refcounts: false I will read up some more on preallocation though and hopefully find all the answers I need. Thanks for your help looking at this, Keelan
Rich.