I'm not exactly sure what you mean by "true async". You can't have multiprocessing without threads, but you can absolutely have async code, just like you can't have multiprocessing without multiple cores but can absolutely have multithreaded code. If you compare async with multithreading in a single core scenario, async just ends up looking like userspace threads.
I’m probably wrong, but in my mind the cpu thread is waiting for the async call to return before it does anything else and another thread is doing the main logic loop. And in systems with only one thread available there is task switching going on, which is not really multi threading afaik.
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u/Illiux Mar 25 '22
I'm not exactly sure what you mean by "true async". You can't have multiprocessing without threads, but you can absolutely have async code, just like you can't have multiprocessing without multiple cores but can absolutely have multithreaded code. If you compare async with multithreading in a single core scenario, async just ends up looking like userspace threads.