2 ms·
It's not obvious that QEMU's JIT has to be a lot slower, but it is. It may be that Rosetta 2 is just more thoroughly engineered and tuned for Apple Silicon. Am
by jlokier 4y ago
It's not obvious that QEMU's JIT has to be a lot slower, but it is. It may be that Rosetta 2 is just more thoroughly engineered and tuned for Apple Silicon.
Among other things, Rosetta 2 is able to use the CPU's special TSO memory ordering mode, which I think QEMU's TCG cannot use so has to use barrier instructions instead (MTTCG), or run all the virtualised CPU threads on a single host core (obviously slower for parallel workloads).