> Emulators can run a different architecture between the host and the guest, but simulate the guest operating system at about 5x-10x slowdown.
I think this is a misleading statement because it implies that there is a constant performance overhead associated with CPU emulation. In reality, the performance relies heavily on the workload, more so with JIT-ed emulators.
Regarding this specific benchmark, I think there are two main factors contributing to the poor performance. The first factor is that the benchmark completes in a short period of time. With JITs, performance tends to improve for long running processes because JITs can cache translation results allowing you to amortize the translation overhead. Another factor is that your benchmark is especially heavy on I/O, meaning that it spends a lot of time translating syscalls instead of running native instructions.
I'd also like to add that CPU emulators sans syscall translation should work for any binaries, even those targeted for Linux. It would require a copy of the Linux kernel, but Docker won't work without it anyways.
> Emulators can run a different architecture between the host and the guest, but simulate the guest operating system at about 5x-10x slowdown.
I think this is a misleading statement because it implies that there is a constant performance overhead associated with CPU emulation. In reality, the performance relies heavily on the workload, more so with JIT-ed emulators.
Regarding this specific benchmark, I think there are two main factors contributing to the poor performance. The first factor is that the benchmark completes in a short period of time. With JITs, performance tends to improve for long running processes because JITs can cache translation results allowing you to amortize the translation overhead. Another factor is that your benchmark is especially heavy on I/O, meaning that it spends a lot of time translating syscalls instead of running native instructions.
I'd also like to add that CPU emulators sans syscall translation should work for any binaries, even those targeted for Linux. It would require a copy of the Linux kernel, but Docker won't work without it anyways.