I’ve made a test to find the best “compressed” solution for thin provisioning on virtual machines.
f18.qcow2 is a default minimal Fedora 18 installation.
$ qemu-img info f18.qcow2 image: f18.qcow2 file format: qcow2 virtual size: 20G (21474836480 bytes) disk size: 1.1G cluster_size: 65536
Below is the result, sorted by size
1170252 f18.qcow2 746188 f18.qcow2.spars 253552 f18.qcow2.spars.compressed 236860 f18.qcow2.spars.compressed.lrz 236076 f18.qcow2.spars.compressed.xz 151028 f18.qcow2.xz 146172 f18.qcow2.spars.xz 141276 f18.qcow2.spars.lrz 141048 f18.qcow2.lrz
It seems that Con Kolivas has made an extraordinary work with lrzip
And these are the commands i’ve run (sorted by the result of above output):
| f18.qcow2 | qemu-kvm f18.qcow2 -cdrom Fedora-18-x86_64-netinst.iso -cpu host -usbdevice tablet -m 2048 |
| f18.qcow2.spars | virt-sparsify f18.qcow2 f18.qcow2.spars |
| f18.qcow2.spars.compressed | virt-sparsify - -compress f18.qcow2 f18.qcow2.spars.compressed |
| f18.qcow2.spars.compressed.lrz | lrzip f18.qcow2.spars.compressed |
| f18.qcow2.spars.compressed.xz | xz -k f18.qcow2.spars.compressed |
| f18.qcow2.xz | xz -k f18.qcow2 |
| f18.qcow2.spars.xz | xz -k f18.qcow2.spars |
| f18.qcow2.spars.lrz | lrzip f18.qcow2.spars |
| f18.qcow2.lrz | lrzip f18.qcow2 |
My specs are:
$ grep 'model name' /proc/cpuinfo | head -1 model name : Intel(R) Core(TM) i7-3517U CPU @ 1.90GHz $ grep -c processor /proc/cpuinfo 4 $ grep MemTotal /proc/meminfo MemTotal: 8038060 kB