I ran OSX on QEMU/KVM on a Ryzen emulated to be an IceLake Intel cpu and got close to ~90%+ performance of my native machine according to geekbench.

So my QEMU OSX instance got better performance than a Mac Pro max, very well near the top ~5 scores for macs in geekbench.

Props

Dracophoenix

What version of MacOS? Did your IceLake emulation require OpenCore and modified kexts or did you achieve by some other process? Were there any notable compatibility issues with any specific hardware or software?

whb07

Take a look here https://github.com/kholia/OSX-KVM. Post install, I use the "Opencore-Boot.sh" script to boot the machine and inside of it modify the cpu "Penryn" to Icelake one assuming you're running a Ryzen one.

I did get some warnings from QEMU along the lines of "X register doesnt exist" or something but the machine runs fine and geekbench runs fine as well. Play with the cores/threads settings as well. If you go too high (for me was around 8), it doesn't boot up and just hangs.