[zeromq-dev] exiting without missing messages

[Pieter Hintjens]

On Sat, Aug 20, 2011 at 8:29 AM, Mathijs Kwik <bluescreen303 at gmail.com> wrote:

> So I would rather keep the system simple. I don't mind adding extra
> sockets so parts can signal each other about adds/removals, but as far
> as I can tell, zeromq doesn't provide means to do this (disconnect /
> remove 1 peer from load-balancer).

This is actually the basis for the REQ/REP reliability as well. Look
at the LRU queue pattern to start with. Now, you can use a
ROUTER-to-DEALER model, with several alternative ways to know when a
worker is present or absent:

- heartbeating
- credit based flow control (see http://unprotocols.org/blog:15)
- synchronous stepping (LRU)

You could also have explicit "bye bye" messages from workers to the
ventillator but that fails to handle the case where a worker actually
crashes.

-Pieter