> You're assuming that an async event context switch is somehow vastly less costly than an OS context switch They are, and this is the entire premise green thr

> You're assuming that an async event context switch is somehow vastly less costly than an OS context switch They are, and this is the entire premise green threads are built on. An OS context switch has to do a lot more including switching page tables and possibly performing a TLB flush. (I do agree that the majority of python projects will get by just fine with regular threads though)