[zeromq-dev] Handling high socket or connection counts

Goswin von Brederlow goswin-v-b at web.de
Mon Feb 10 10:52:58 CET 2014

On Fri, Feb 07, 2014 at 09:32:14AM +0100, Olaf Mandel wrote:
> Am 06.02.2014 18:50, schrieb Michel Pelletier:
> > It's true a client can only make ~60K outgoing connections (due to
> > ephemeral port exhaustion) but a server with bound sockets can have up to
> > 64K connections _per port_.  Here's a blog post from urban airship
> > detailing their experiments with pushing connection limits up to 500K on a
> > single machine:
> > 
> > http://urbanairship.com/blog/2010/08/24/c500k-in-action-at-urban-airship/
> -Snipp-
> > I was wrong by a similar order of magnitude, it's per port per client.
> > 
> > http://stackoverflow.com/questions/2332741/what-is-the-theoretical-maximum-number-of-open-tcp-connections-that-a-modern-lin
> > 
> > It's basically unlimited.
> -Snipp-
> Hello,
> thank you for the two links: the stackoverflow post certainly answers
> the question of number of connections allowed. And the urbanairship post
> actually gives me a feeling what kind of performance to aim for :-)
> Best regards,
> Olaf Mandel

Since the conection is from localhost to localhost every incoming
connection to the server is also means one outgoing connection.

Unless, as said, you use container, virtual machines or seperate hosts
to have different IPs to connect from.


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