I have a qube, it is usual PVH, template-based, default kernel, I see nothing special.
And it has:
- private storage max size 160 GiB (I’ve been using this space, but later removed data from it).
- actual data on
/rw: ~ 0.1 GiB
/ is default 9.6 GiB.
I would expect the resulting backup of the qube to be about 0.1 GiB, as happens with all other qubes, but in case of these one
qvm-backup produces backup of 20 GiB size.
How can I get it smaller?
Is it some LVM-thin-provisioning problem?
Is this from looking at it inside the VM, or is it equally small if you check with
qvm-volume info VMNAME:private usage in dom0?
If that command reports a much larger (byte) size than expected even after accounting for filesystem overhead, try running
sudo fstrim /rw inside the VM.
It is according to
Your command shows huge size (28 GiB).
sudo fstrim -v /rw
/rw: 0 B (0 bytes) trimmed
I also run
sudo fstrim -av as @brendanhoar suggests here (so I hope it will not affect other partitions in any bad way), but the output was similar: 0 bytes trimmed. Nonetheless, after shutdown of the qube its size according to
qvm-volume was reduced 100 times! Strange.
fstrim is about ssd TRIM, was not thinking about effects on LVM.
So, thank you, @rustybird.
I am still curious, why was it happening in the first place, why isn’t
fstrim scheduled (I am using template based on fedora-minimal, maybe that is the reason).