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Comment by ArgyleSound | Hacker News Reader

To be fair they're both 8 core big.LITTLE processors but the Apple chip is running the benchmark under x86 emulation and thus isn't able to use asymmetric cores, only the four performance ones.

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I was under the impression that Rosetta 2 is install-time translation and thus not emulation at all...

I think it does both, but I'm not familiar with what Geekbench 5 actually does and whether it can be fully translated ahead of time. Regardless the translation doesn’t seem to be able to make use of both sets of cores.

Maybe Apple will release more detailed information in the near future. I'm curious to learn what the differences between Rosetta 2 and Microsoft's emulation technique are.

Yeah. Presumably more information will also trickle out from the developers who are using the DTKs.

Trickle, of course. The details are still under NDA.

What is the difference supposed to be anyway?

It's user-mode emulation of x86_64 whether the translation happens just-in-time or ahead-of-time. AOT just can afford to spend more time optimizing out redundant emulation operations in each basic block.

It's not emulating privileged modes or devices, but neither is Microsoft's emulation (or user-mode QEMU for that matter.)

I was under the impression that the said system works more like a compiler than a interpreter.

Sure, no emulator serious about performance uses an interpreter these days. Even full-system emulators.

Even if you ignore the problem of self-modifying code, a completely static translation of x86 binaries is impossible. Things get hard real quick when indirect branches are involved, so you have to rely on a runtime solution when ahead of time solutions won’t work.

It's both. Install-time translation, plus runtime emulation for code that the system didn't get to translate (JIT, newly compiled applications, runtime loaded or obfuscated code, applications running from non-local storage, etc).

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