FX Logix error: Disk was not compacted, Reason: Not enough recoverable space for compaction.

Question

Hi support,

We recently setup a GPO for compressing/compacting VHDX's for a client of ours with the setup below:

When checking the logs the below shows for most users:

Profile removed for sid S-1-5-21-3676007091-1767207455-1883875831-1972 Disk size results: WasCompacted: false, MaxSupportedSize: 31456214528, MinSupportedSize: 19213524480, SizeOnDisk (Before: 22988980224 - After: 22988980224), Space Saved: 0, Compaction took: 1031 Disk was not compacted, Reason: Not enough recoverable space for compaction.

I compared a few sources and worked out the below sizes for the VHDX:

Max Support Size: 31456214528 (31.4GB) Min support Size: 19213524480 (19.4GB) Size on Disk: 22988980224 (23GB) Size on Disk in TreeSize: 17.6GB Size on Disk in Disk Management: 29.30GB

Although the sizes vary for the ones mentioned above, I believe the issue is that the user's VHDX is trying to compact by lowering its current size with the additional space from expanding (23GB) to its actual size (17.6GB), but since it has the Minimum Support Size Threshold of 19.4GB, there isn't enough space for the compaction as it needs 1.8GB more to meet the minimum requirement.

I did read that a few factors come into play here, such as there needing to be 20% of free space on the VHDX from its minimum, or if the VHDX is a differencing disk and changing the Profile Type and/or VHDAccessMode values in the link below:

https://learn.microsoft.com/en-us/fslogix/troubleshooting-vhd-disk-compaction#unexpected-vhd-disk-compaction-results

However, I'm not sure which values I should change and where these can be changed.

My question is if there's a way of changing the Minimum Support Size of all VHDX's (client has 50+ VHDX files) so it can compact properly? Or what values need to be changed so the VHDX's can compact?

Thank you in advance!