Currently seeing approximately 0.5 million messages per second,
with only two threads, on a Intel i7 Quad Core 4700HQ 2.4 GHz.
See unit tests for usage.
Currently unsupported (big items missing):
Remoting and Clustering (LocalActorRef/RemoteActorRef)
Creating and stopping actors is currently not asyncrhonous,
and the ActorKilledException/Stop messages are currently
not supported. Further, if a message is delivered to a
suspended actor (e.g. due to a restart) the delivery
currently blocks rather than stashing messages. This is
because stashing would require another incoming message
to cause the stashed messages to be delivered. A scheduler
would be the thing to cause the stash to be emptied. The
good news is that the block is a sleep and will likely
last only one 1 ms interval.