[zeromq-dev] High water mark notification for publisher

[Paul Colomiets]

Hi Edwin,

On Sun, Sep 23, 2012 at 6:23 AM, Edwin Amsler
<edwinamsler at thinkboxsoftware.com> wrote:
> I have a mechanism out of band over TCP that re-requests pieces once the
> transfer is done, but I'm never actually sure when it's done sending so I
> just wait 1 minute before re-requesting.
>
> If I had some indicator of whether or not the message goes missing, I could
> re-transmit or throttle back the 500MB/s to what the network is actually
> able to provide.
>

I think you can also have an out of band pub-sub over TCP to send acks
from clients to server. You need some way to count acks (e.g. clients
may send presence notification before start of a transfer). But it may
give you a way to limit bandwidth in more automatic way.

You may also look at ZMQ_RATE and ZMQ_RECOVER_IVL options, they should
(theoretically) give you reliability without out of band socket to
request data, however I don't know how well that works in practice.

-- 
Paul