[rabbitmq-discuss] Consumer acknowledgements for very long running tasks

Thu May 2 10:42:07 BST 2013

On 01/05/13 20:33, Michael Klishin wrote:
> 2013/5/1 ranjitiyer <ranjitiyer at gmail.com <mailto:ranjitiyer at gmail.com>>
> 
>     Is there a corner case in which because acks haven't been received for a
>     very long time, msgs are either automatically redelivered or 'considered
>     consumed'?
> 
> AFAIK there are no limitations on how long the broker will wait for 
> acks, but if you use queue TTL, it may affect your case.

Further to what Michael says, queue TTL only applies when a queue is
unused. In this case a consumer will exist while the message remains
unacknowledged so the queue will not be unused and queue TTL does not
come into play.

http://www.rabbitmq.com/ttl.html#queue-ttl

Network interruptions will cause the unacknowledged message to be
returned to the queue. Over a period of a month this becomes a real
possibility.

-Emile