[packetlost]

> multithread scalability is a well understood, if not easy, problem

As someone fairly well versed in MESI and cache optimization: it really isn't. It's a minority of people that understand it (and really, that need to).

> Building your application on top of message passing not only gives away some performance

This really isn't universally true either. If you're optimizing for throughput, pipelining with pinned threads + message passing is usually the way to go if the data model allows for it.

[gpderetta]

To be clear, I'm not claiming any universality. Quite the contrary, I'm saying that there is no silver bullet.