# Compact VM disk images Note that disk images can only be compacted if they are *not* in a snapshot chain and do *not* use disk encryption! ## libVirt ```bash virt-sparsify --compress /path/to/image.qcow2 /path/to/new-image.qcow2 ``` ## VirtualBox ### Windows Disable the paging file (**Settings > System > About > Advanced system settings > Advanced > Performance > Settings... > Advanced > Virtual memory > Change...**), clean all temporary files (**C: > Properties > Disk Cleanup**), defrag (`defrag C: /FreespaceConsolidate /Verbose`), and then zero out free space with [SDelete](https://docs.microsoft.com/en-us/sysinternals/downloads/sdelete) (`sdelete -z C:`). Then, compact the disk image on the host: ```bash vboxmanage modifymedium /path/to/image.vdi --compact ``` Remember to turn the paging file back on after compacting the drive! ### Linux Zero out free disk space *on the guest*: ```bash sudo dd if=/dev/zero of=/temp.zeros bs=4096k sudo rm -f /temp.zeros ``` Compact the disk image *on the host*: ```bash vboxmanage modifymedium /path/to/image.vdi --compact ```