[rabbitmq-discuss] Message sending/receiving overhead.

Thu Aug 1 03:21:25 BST 2013

Pavel,

On 31/07/13 23:16, Pavel Kogan wrote:
> However publishing response in line with processing slows the things as
> network latency is considerable (even though it is internal 1Gbit
> network).

Publishing is an asynchronous operation and therefore should not be 
affected by latency.

> The question is about receiving overhead. Is there any pre-caching of
> messages [...]?

By default there is an infinite prefetch, i.e. the broker will send 
messages to the client as fast as network speed & server processing 
permits. The number of messages "in flight" that way, more precisely, 
the number of messages that have been sent to the client but not yet 
acknowledged, can be bounded with the basic.qos prefetch setting. See 
the section of "Fair dispatch" in Tutorial #2 
(http://www.rabbitmq.com/tutorials/tutorial-two-python.html).

Matthias.