[zeromq-dev] Need for Late join and End of source detection
RohanB
rohanb at cs.uchicago.edu
Mon Oct 1 21:13:29 CEST 2012
Hi All,
I'm trying to use ZeroMQ with OpenPGM. Coming from a proprietary messaging
solution I've been spoiled with two very important features they provided - EOS
(end of source) and Late Join Cache. Let me explain them here.
1) Late Join Cache:
In a reliable multicast pub-sub environment, late join caches allows subscribers
that join much late to receive the last published update on that topic. Let me
explain further. Lets say a publisher is publishing non-frequently changing
state. If such updates are very infrequently published, subscribers that join
late may have to wait a while to get the next update. In this situation, late
join cache on the publisher side allows the publisher to automatically publish
the last known update on that topic when it detects that a subscriber has just
joined. This ensures that all subscribers get at-least one last known update, if
it was ever published, no matter how long ago.
2) EOS:
End of source quite simply generates an asynchronous event on the subscriber
side when the last publisher on that topic has gone down. This is made possible
by a heartbeat that goes on under the covers between each subscriber with the
publisher once connected.
I was wondering if there is support for these features in ZeroMQ. If not are
there any plans to include the same in upcoming versions? Wondering if anyone
has other solutions to these problems.
Much appreciated,
Rohan
More information about the zeromq-dev
mailing list