Getting 'Allocation' down on a previously full VM disk

[peewee67]

Short introduction: i have been a Synology user for 15 years. Lately i realized i'm using more and more Docker containers and VMs for my needs, and less the built in Synology tools. So i'm giving Unraid a try on a second hand Intel Nuc i bought, and i'm very impressed and conside rmaking the move to Unraid.

 

I have set up a VM with a qcow2 VMdisk of 100GB with a xfs filesystem. I nearly filled that VM disk experimenting but need around 30G as a baseline. I'm not bothered by the 'Capacity' of 100GB that the Vdisk could claim over time, but i would like to get the 'Allocation' number back down to the 30GB which is currently in use. I have added discard='unmap' to the XML of the VM and started the TRIM process from the Unraid settings. I also ran a xfs_fsr defrag in the VM, but the allocation doesn't come down in Unraid. Is there anything else i should do?  As far as i understand, i won't be needing to shrink the VM disk or the volumes inside it to make this happen, because when i epxanded the Vdisk earlier, the allocation only shot up once i started filling the vdisk with data. 

[JorgeB]

40 minutes ago, peewee67 said:

I have added discard='unmap' to the XML of the VM and started the TRIM process from the Unraid settings.

You need to run Trim in the actual VM, if it's Windows run the Defrag and Optimize disks tool

[peewee67]

Thanks!, all that was needed was to run 'fstrim -v /'  in the VM, thanks alot!