[VHD] Expandable VHDX Disk Remains Expanded and Cannot Be Compacted

Question

Hello,
I've noticed that one of my VHDX virtual disks storing Windows Server 2008 R2 and attached to a virtual machine remains expanded and consumes maximum space assigned on creation even when this virtual machine is turned off.
The diskpart confirms disk is expandable:
Notice, the VDisk 1 pointing to the win2008r2dc.vhdx file is expandable.
However, looking at the disk size in Windows Explorer shows that the disk remains expanded to its maximum capacity even though it's not in use (I've detached the disk before viewing the disk files in Windows Explorer):
The disk highlighted in blue allocates all 100 Gbytes! You may see here that there's another one 100 Gbyte VHD disk (not VHDX one) --- the win8rp.vhd storing Windows 8 Release Preview, which is also used in a virtual machine,--- is allocated to roughly
67 Gbytes although it's an expandable virtual hard disk drive with a limit of 100 Gbyte.
Why does the win2008r2dc.vhdx allocate all its size and does not collapse to its actual size? I've checked the drive with scandisk and it does not show any errors.
Thank you.
Well this is the world we live in And these are the hands we're given...

Answer 1

Hello,
I've noticed that one of my VHDX virtual disks storing Windows Server 2008 R2 and attached to a virtual machine remains expanded and consumes maximum space assigned on creation even when this virtual machine is turned off.
The diskpart confirms disk is expandable:
Notice, the VDisk 1 pointing to the win2008r2dc.vhdx file is expandable.
However, looking at the disk size in Windows Explorer shows that the disk remains expanded to its maximum capacity even though it's not in use (I've detached the disk before viewing the disk files in Windows Explorer):
The disk highlighted in blue allocates all 100 Gbytes! You may see here that there's another one 100 Gbyte VHD disk (not VHDX one) --- the win8rp.vhd storing Windows 8 Release Preview, which is also used in a virtual machine,--- is allocated to roughly
67 Gbytes although it's an expandable virtual hard disk drive with a limit of 100 Gbyte.
Why does the win2008r2dc.vhdx allocate all its size and does not collapse to its actual size? I've checked the drive with scandisk and it does not show any errors.
Thank you.
Well this is the world we live in And these are the hands we're given...
I found that large VHDX files (64TB allocated) will grow but I use smaller ones for VDI VMs.
if you need to run with lots of VHDX files, you are advised to get lots of storage, lots of it
low cost NAS boxes are one suggestion
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