Shrink qcow2 file with Windows guest


  1. Remove unnecessary file and empty the recycle bin in windows guest.
  2. De-fragment your disk in windows guest. You may do it several times for good compact status.
  3. Free unused disk space in windows guest.
    sdelete -c c:
  4. Convert the disk image itself.
    qemu-img convert -c -O qcow2 win.qcow2 win-shrinked.qcow2


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