Is it possible to convert an "Apple Virtualisation" image to "QEMU"

[PicoCreator]

1. Is the "Apple Virtualisation" mode in UTM using QEMU underneath the hood - or simply bypassing it and integrating straight to apple code.

2. Is it possible to convert an existing "Apple Virtualisation" image to a QEMU image - if so what are the process to do so?

Side note: Damn the "Apple Virtualisation" performance was surprisingly good, and I would like to do some apple to apple benchmarks against QEMU. Especially on GPU related workloads

[iustin]

I would be interested as well on this, also on Qemu→Apple conversion. The disk contents shouldn't be impacted, but maybe needs conversion from qcow2 to something else.

[crasm]

I was able to convert to raw format successfully.

$ cd Library/Containers/com.utmapp.UTM/Data/Documents
$ qemu-img convert -f qcow2 -O raw "Linux.utm/Data/<qemu-disk-UUID>.qcow2" "Linux 3.utm/Data/<hvf-disk-UUID>.raw"

My qcow2 image was sized for up to 64GB but the converted raw image was only the 12GB or so I already had. Latency, performance, and graphics are much better, but it ended up for naught in my case because USB passthrough isn't supported.

[mikemallin]

I can't answer #1, but it is possible to convert a HVF raw image using qemu-img:

qemu-img convert -f raw -O qcow2 <Path/To/HVF/Disk.img> ~/output-img.qcow2

I'd suspect the reverse should also hold to go from Apple to QEMU.

[RonGros]

Did you ever test that? does it work?

[mikemallin]

I've only tested from img to qcow2 using a dev vm on my laptop. I haven't tried the reverse.

[proski]

Conversion from RAW only works is "Use Apple Sparse Format" was unchecked when the image was created. If the image is in sparse format, it cannot be converted by qemu-img (the conversion would produce an invalid image). One way to deal with it is to add an uncompressed image of the same size and a bootable ISO to the VM, boot from the ISO and copy the disk. Then make qcow2 from the uncompressed image. I tested it for a simple Alpine install.

There is also Apple's hdiutil, but it also supports uncompressed images only.