Because QCOW2 expands dynamically, deleting files inside Windows 10 does not automatically shrink the QCOW2 file on the host. To fix this, enable support: Ensure your disk bus is set to VirtIO SCSI .
# Compress and shrink the file qemu-img convert -O qcow2 -c windows10.qcow2 windows10_compressed.qcow2 # Replace the old file with the optimized one mv windows10_compressed.qcow2 windows10.qcow2 Use code with caution. Summary Comparison: QCOW2 vs. Other Formats VHDX (Hyper-V) Dynamic (Thin) Thick (Immediate) Dynamic / Thick Snapshots Native (Internal) Performance Excellent (with VirtIO) Portability Universal (KVM/QEMU) Windows-centric Troubleshooting Common Issues VM Boots to a Blue Screen (BSOD) Cause: Incorrect storage bus selected after installation. windows 10qcow2
Speed up your workflow and keep your test environments clean. Because QCOW2 expands dynamically