[SOLVED] Storage usage

[milanv]

Hi after getting new server, Im migrating VMs and Containers from one PVE node (8.3.4) to another (8.4.1). On 8.3.4 they live on ZFS raid1 2TB pool, on 8.4.1 they have 4TB ZFS raid1 pool. As recommended Im doing the migration via PBS.

What confuses me a lot is if I run zfs list -o name,used,logicalused,referenced,compressratio on both nodes i get for example on vm-112:
NODE: NAME USED LUSED REFER RATIO
8.3.4: rpool/data/vm-112-disk-0 44.4G 60.0G 44.4G 1.36x
8.4.1: ZFS_Mirror_1/vm-112-disk-0 102G 55.7G 35.5G 1.57x

* to note here the vm-112 is windows server 2019, in guest os C drive is like ~100G, 60full/40free. The vm config is identical (as expected after PBS restore), with
sata0: ZFS_Mirror_1:vm-112-disk-0,discard=on,size=100G,ssd=1
scsihw: virtio-scsi-pci

Why is the used on 8.4.1 twice the size? It looks like the thin provisioning is not working? Have I missed something?

 

[milanv]

On Node - Disks - ZFS i get Allocated 635.81GB, Storage - Summary - Usage 1.74TB.
I guess its directly related to what I have described above. What Im looking at here?

 

[milanv]

The thin provisioning on zfs storage was not enabled i guess i need to start migrating over again

 

[Impact]

No need, just set the refreservation property of the existing datasets/ZVOLs.
Check zfs list -o name,used,avail,refer,mountpoint,refquota,refreservation.

 

[milanv]

Is there an easy way, how to recreate the VM volumes to start using the thin provisioning without restoring over network from PBS again?

 

[Impact]

You can use something like this

zfs list -H -oname,refreservation | grep -Ev "none" | awk '/vm-/ {print $1'} | while read disk; do echo "zfs set refreservation=none $disk"; done

It's not pretty but that should print out a list of commands for datasets/ZVOLs with refreservation or name not containing none.
Run the command(s) to enable thin provisioning for the dataset/ZVOL. Verify with the command from my post above.