title: Does Erlang always copy messages between processes on the same node?
body: <p>A faithful implementation of the actor message-passing semantics means that message contents are deep-copied from a <em>logical</em> point-of-view, even for immutable types. Deep-copying of message contents remains a bottleneck for implementations the actor model, so for performance some implementations support zero-copy message passing (although it's still deep-copy from the programmer's point-of-view).</p>
  
  <p>Is zero-copy message-passing implemented <em>at all</em> in Erlang? Between nodes it obviously can't be implemented as such, but what about between processes on the same node? <a href="https://stackoverflow.com/questions/3391274/how-does-erlang-pass-messages-between-processes-on-the-same-node">This question</a> is related.</p>