qcow2 images not shown as dynamic but max size?
from Pantherina@feddit.de to linux@lemmy.ml on 30 Nov 2023 17:58
https://feddit.de/post/6220263

I am on Fedora with KDE (Kinoite) and use virt-manager.

I like to test a lot of stuff, but the VMs are not big. As they are dynamically allocated, I create them with 50GB or something.

But it seems that virt-manager and also KDE Dolphin see these qcow2 images as being full size, so I currently have only 20GB of “space left”.

Do you know anything about this?

#linux

threaded - newest

Mixel@feddit.de on 30 Nov 2023 18:11 next collapse

I think qcow2 images are always a fixed size (but I could be wrong on that) however I saw some threads explaining how you could relatively easy modify the size of the qcow2 image :)

bizdelnick@lemmy.ml on 30 Nov 2023 18:26 next collapse

I did not use virt-manager for a while, but probably it allocates the whole virtual disk by default (i don’t remember for sure). Try to create it manually and ensure that checkbox “allocate the whole volume” is disabled. You can also do this with qemu-img create command (see man qemu-img for options).

bizdelnick@lemmy.ml on 30 Nov 2023 19:26 next collapse

BTW it is possible to compress existing qcow2 images. Before that I recommend to run fstrim -a inside the VM. Then shut it down and execute qemu-img convert -cp old_image.qcow2 new_image.qcow2 && mv -f new_image.qcow2 old_image.qcow2.

Pantherina@feddit.de on 01 Dec 2023 13:35 collapse

Thanks!

[deleted] on 30 Nov 2023 20:05 collapse

.

Pantherina@feddit.de on 30 Nov 2023 20:33 collapse

Hmm. Maybe? This would be a virt-manager but though, as I stopped bothering with CLI and just use that again