Am 20.10.2020 um 03:31 hat Wang, Wei W geschrieben: > Hi, > > Does anyone know the reason why raw-format.c doesn't have compression > support (but qcow has the supported added)? For example, raw image > backup with compression, "qemu-img convert -c -O raw origin.img > dist.img", doesn't work.
A raw image is by definition a file that contains the exact same sequence of bytes as the guest sees, without any additional information or encoding. If you compress a raw file, the guest will see compressed data on its hard disk instead of the real data. Anything you could do to add transparent compression to it would mean that it's not a raw image any more, but a new image format. Kevin
