[SOLVED] Disk usage is low but VM backup is huge


New Member
May 26, 2023
Hi all,
I have a VM I backup regurlarly; this VM has a disk of 700GB.
But real disk usage is only about 50GB.
So far, backup sizes were very reasonable (about 20-30GB) but it jumped to 150GB for last backup.
I guess it's because I had to temporarily copied a big file(120GB) to this 700GB disk and then I removed it prior to backup.
However, this "file" is still in the backup.
Is there a way to clean-up a disk before making a backup (such as zero non referenced space)?
Or is there any smart solution to avoid backing-up non longer relavant data?
Hi again,

finally found the command:
sudo fstrim -av
to perform this.
Should have looked deeper before :)
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