On Wed, Jun 15, 2016 at 10:20:54AM -0500, libvirt_users@xxxxxxxxxxxxxxx wrote: > Hello, > > I am curious why when using virt-sparsify the apparent-size of the file > gets reduced to the actual file size? Is there a way to get the > apparent-size left as the full size? > > In the man page for virt-sparsify it has a section on > "IMPORTANT NOTE ABOUT SPARSE OUTPUT IMAGES" and its output seems to > indicate what I would expect where "ls -lh" shows the full apparent size > and "du -sh" shows the actual size. But my actual results from testing > are different. > > In the following example input.qcow2 is before sparsify and output.qcow2 > is after. > > Doing ls reports full size for input but a small size for > the output: > root@testingbox:/tmp/test # ls -lh > total 3.1G > -rw-r--r-- 1 root root 512M Jun 14 22:30 file.img > -rw-r--r-- 1 root root 51G Jun 14 22:30 input.qcow2 > -rw-r--r-- 1 root root 790M Jun 14 22:36 output.qcow2 What is file.img? > Same when asking du for apparent-size: > root@testingbox:/tmp/test # du -h --apparent-size * > 512M file.img > 51G input.qcow2 > 790M output.qcow2 'du --apparent-size' and 'ls -l' are the same thing, so it's not really surprising that you see the same numbers here. > A normal du will show the actual size of the files: > root@testingbox:/tmp/test # du -h * > 0 file.img > 2.4G input.qcow2 > 790M output.qcow2 > > The only way I have found to check the full virtual size of the file > after virt-sparsify is with qemu-img: > root@testingbox:/tmp/test # qemu-img info input.qcow2 > image: input.qcow2 > file format: qcow2 > virtual size: 50G (53687091200 bytes) > disk size: 2.3G > cluster_size: 65536 > Format specific information: > compat: 1.1 > lazy refcounts: true > root@testingbox:/tmp/test # qemu-img info output.qcow2 > image: output.qcow2 > file format: qcow2 > virtual size: 50G (53687091200 bytes) > disk size: 789M > cluster_size: 65536 > Format specific information: > compat: 1.1 > lazy refcounts: false If I understand your question correctly, then everything is working as it should. For qcow2 files, the virtual size is not related to the "apparent" size, as you can easily prove: $ qemu-img create -f qcow2 huge.qcow2 1T Formatting 'huge.qcow2', fmt=qcow2 size=1099511627776 encryption=off cluster_size=65536 lazy_refcounts=off refcount_bits=16 $ ls -lh huge.qcow2 -rw-r--r--. 1 rjones rjones 208K Jun 17 09:09 huge.qcow2 If you use raw files, then the file apparent size and virtual size are the same. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org _______________________________________________ libvirt-users mailing list libvirt-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvirt-users
