[mgaunard]

Well in mine for example, threads are pinned to a core and always spin, and actors are pinned to a given thread (you can have an arbitrary number of actors per thread, they're just objects), so "waiting" is certainly not something you'd use to describe the setup in any capacity.

[d4ng]

What happens when there are no messages on the queue for a given actor?

[mgaunard]

An actor does not have a queue; that's again the whole point I already made: it's event-driven, things are decoupled and the actor is not aware of how control flow happens.

Regardless, when the queue which exists and is per-thread is empty, the program terminates.