the scheduler is probably simpler if coroutines can't bounce between cores. you can have a single thread per core that runs the scheduler to multiplex a bunch of coroutines on the single thread, which lines up with the example linked in the repo to a redis clone. redis runs a single thread (i think technically it has some multithreading stuff now but that was the model for a while) but can concurrently process a bunch of requests like when 1 or more requests are blocked on blpop, a pubsub thing, xread with block arg given, etc. nginx does something similar with forking a process per core that runs single threaded (ignore the threading for stuff that reads from disk).