[rabbitmq-discuss] What happens to messages delivered just before canceling consume?

Chris ctlajoie at gmail.com
Fri May 18 19:25:25 BST 2012


On Fri, May 18, 2012 at 4:41 AM, Matthew Sackman <matthew at rabbitmq.com> wrote:
> However, unless you are on a network with 0 latency, a prefetch of 1
> will guarantee your client sits around idle for at least some of the
> time. If you follow the maths through on my recent blog post,
> http://www.rabbitmq.com/blog/2012/05/11/some-queuing-theory-throughput-latency-and-bandwidth/
> then you should be able to calculate a sensible prefetch figure (without
> resorting to more exotic solutions like CoDel).

Thank you for linking the blog post.. very informative. I had not
thought about the potential consequences of using a prefech of 1, but
you clearly explained the tradeoffs.

Obviously no one is on a network with 0 latency, but all nodes of my
application are on the same (small) LAN, and will have low latency.
Also the time it takes to process a single message received by one of
my consumers can vary wildly, from about 1 second to 15 seconds, and
it is important that they get processed ASAP, even though they can
take this amount of time. In this situation do you believe I am
justified in using a prefetch count of 1?

Chris


More information about the rabbitmq-discuss mailing list