[zeromq-dev] Basic questions about PUB-SUB

[Pieter Hintjens]

On Fri, Apr 26, 2013 at 2:19 PM, Nishant Mittal <nmittal at rblt.com> wrote:
> In a pub sub scenario in 3.2.2
> 1) does the filtering happen on the Publisher (i think yes) or the
> Subscriber?

Yes, the publisher filters.

> 2) does number of subscribers effect performance of the publishers (I think
> yes, as the pub has to filter/send msgs to all subscribers)

Not really, your network will saturate before the publisher is affected.

> 3) I send out 3 part msgs.. 1st 2 parts are really for filtering and the 3rd
> part is a binary object.. when I subscribe.. would zeromq try to match with
> all 3 parts?..

No. the match stops at the end of the first frame in the worst case
(and stops when it mismatches a single octet anyhow).

-Pieter