[SOLVED] VM Disk consuming more space than assigned ?

[dariuszszyc]

Hello,

Proxmox 7.4-17

I have usb NVME drive added as ext4 partition on which I have only 1 VM Disk.
There is nothing else on that drive (see NCDU below).

It's assigned to VM as 650 GB and I think ~698 GB Size indicated might be ok, but I don't understand why the size usage of that NVME is constantly growing and almost took all the capacity...











Here's what NCDU says...





After some advices from Reddit - I enabled the "Discard" option and ran fstrim. I also ensured it is executed weekly.

/usr/sbin/fstrim --fstab --verbose

Gave this response:

/srv/dev-disk-by-uuid-112a8316-67e8-4785-8ead-af534f82012f: 81.4 GiB (87449911296 bytes) trimmed on /dev/disk/by-uuid/112a8316-67e8-4785-8ead-af534f82012f

OpenMediaValut is the VM and it shows this :


I also had suggestion to load big file on that drive and remove it to force trim (after setting drive to Discard in Proxmox).

Didn't help.

So my 650 GB Disk, which according to OMV has 570 GB used space - in Proxmox still shows that it takes ~940 GB.

I loaded a 4GB file, but that increased the used space on Proxmox to 934GB.
Removed the file and ran fstrim again to see what happens - I'm back to 930 GB

I've read that this could be also a consequence of making backups using Proxmox snapshot mode, so I've changed backups of that VM to "Stop" mode, however this disk isn't part of the Backup.

 

[gfngfn256]

I believe there are probably snapshots being stored within/with the copy-on-write image, see here.
If you show the {VMID}.conf file you'll probably/possibly find the snapshots.

 

[dariuszszyc]

I believe there are probably snapshots being stored within/with the copy-on-write image, see here.
If you show the {VMID}.conf file you'll probably/possibly find the snapshots.

I noticed the discard option on the HDD_4TB so I took it out as it's not SSD.

 

[gfngfn256]

Hmm, so assuming that's the complete {VMID}.conf file (doesn't continue further down) - can't see any snapshots here. What about somewhere in GUI?
What does a full ls -R of that /images directory show.

 

[dariuszszyc]

Hmm, so assuming that's the complete {VMID}.conf file (doesn't continue further down) - can't see any snapshots here. What about somewhere in GUI?
What does a full ls -R of that /images directory show.

That's exactly what I don't understand - I don't know why GUI shows more usage than any other tool.



Could the "Directory" type be an issue ?

 

[gfngfn256]

So what does ls -sh /mnt/usb_lexar/images/105 show?

 

[gfngfn256]

What does qemu-img snapshot -l /mnt/usb_lexar/images/105/vm-105-disk-0.qcow2 show?

 

[dariuszszyc]

 

[gfngfn256]

So a snapshot exists within the qcow2 with the TAG before_update.

I believe the 0 B size shows some error occurred with this snapshot/creation?

Can you see this snapshot in the GUI? ( VMID, Snapshots). Try & remove it there while the VM is shutdown.

If not you could try (while the VM is shutdown) qemu-img snapshot -d before_update /mnt/usb_lexar/images/105/vm-105-disk-0.qcow2

I remember reading once that you could transfer the image to another storage & back again, to get a clean image.



Edit: See here with reference to your situation.

 

[dariuszszyc]

So a snapshot exists within the qcow2 with the TAG before_update.

I believe the 0 B size shows some error occurred with this snapshot/creation?

Can you see this snapshot in the GUI? ( VMID, Snapshots). Try & remove it there while the VM is shutdown.

If not you could try (while the VM is shutdown) qemu-img snapshot -d before_update /mnt/usb_lexar/images/105/vm-105-disk-0.qcow2

I remember reading once that you could transfer the image to another storage & back again, to get a clean image.



Edit: See here with reference to your situation.

I do not see this snapshot in the GUI.
But I do recall there was some issue with snapshot/backup some time ago.
I think I removed it via GUI and thought the problem was solved as it disappeared.
Perhaps it didn't disappear fully.

A little shame this "empty" snapshot isn't visible in the GUI even though it's visible via CLI (something to improve perhaps).

I cannot do the copy thing as I don't have free 1 TB currently
I'll test the command you shared and let you know about results .

 

[gfngfn256]

Make sure you have a (restorable) backup before you "mess" with any VM disk.

 

[dariuszszyc]

Fortunately this VM Disk is only one of my backups

And we have a success !

Thank you ! I've learned something new

 

[gfngfn256]

Happy it worked. Mark the thread as [SOLVED]. (Right-top under title).