Inside Windows: Run Defragment and Optimize Drives -> Optimize (This allows the guest to mark free space).
virt-sparsify --in-place Windows 10.qcow2 Solution: Install the virtio-win-guest-tools inside Windows. Also, allocate dedicated memory to the virtual GPU in virt-manager (e.g., 256MB of Video RAM). Blue screen: INACCESSIBLE_BOOT_DEVICE Solution: Your VM switched from IDE to VirtIO without preparing the registry first. Always add the VirtIO driver before changing the disk controller. Part 9: Backing Up and Migrating Windows 10.qcow2 One underrated benefit of QCOW2 is portability. To back up your entire Windows 10 VM: Windows 10.qcow2
<driver name="qemu" type="qcow2" cache="none" io="native"/> Over time, your Windows 10.qcow2 file grows. Even if you delete files inside Windows, the image file on your Linux host stays large. To reclaim space: Inside Windows: Run Defragment and Optimize Drives ->
On Linux Host: Shut down the VM and run: To back up your entire Windows 10 VM:
Using QEMU directly: