[chrisseaton]

I think the person you're replying to was saying that 'useful work' does not including waking up, reading one value, and then immediately sleeping again for another response. That's a big expensive context switch for really nothing very useful, and it could have waited until all inputs were ready and there was significant computation that could be run.

[Ndymium]

In most cases, BEAM's (the Erlang VM's) context switches are not big and expensive, though, which is something you get with user space threads.