On Mon, Nov 16, 2015 at 3:12 AM, Jojy Varghese <[email protected]> wrote: > A simple such system can be implemented by adding a special message type > called barrier. And once a barrier is received by the receiver, it will have > to acknowledge that packet. Only after the acknowledgement is receiver at the > sender side, will the next packet in the order be sent. This means that > ordering is on-demand and not forced.
Right: if we choose not to provide an ordering guarantee over the message stream between two processes, we could then add a barrier-like primitive to enforce an ordering between any two given messages. As discussed elsewhere in this thread, that is not the current (intended/assumed) semantics, nor what is provided by Erlang/Akka -- we'd need to audit the Mesos code to ensure that any ordering dependencies between messages are explicitly protected by barriers. In theory, supporting ordered, unreliable delivery between two processes shouldn't be that hard, so hopefully we don't need to go down this path. Neil
