[SOLVED] Really strange disk usage !?


New Member
Jan 2, 2020
Good morning all,

I am posting here because there is something that I have never seen and that I cannot understand. I have a VM with an 800 GB virtual disk, however, when I make a "df -h" in the Vm, there is 800 GB available but only 265 GB used. But when I make a backup of this VM or I do a "du -h" on the disk from my proxmox host this VM is more than 650GB. Has anyone ever seen this or knows where this difference can come from?

Thanks in advance,


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1. deleting files inside the vm, does not necessarily free up space on the host, for this you would have to set 'discard' on the disk and do a trim inside (or write zeroes)
2. the config only ever shows the allocated space, never the one actually used
3. qcow2 files are sparse, so they only take up the space they need

i hope this explains the difference :)
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