[rabbitmq-discuss] Evaluating RabbitMQ - a few questions

Thu Apr 30 17:13:09 BST 2009

Brendan Ribera wrote:
>     * Our current system allows us to do a unique constraint on userid

Off the top of my head I don't see a way of doing that with a stock
RabbitMQ. It's effectively the same problem as exactly-once messaging:
sending more than one copy and deduplicating at the ultimate receiver...

>       My question is about ack timing: how long does the worker have
>       before the message is requeued? is this time configurable? is it
>       configurable per queue?

The server will wait for an ack for as long as the connection (actually,
the channel within the connection) survives. If the channel is closed,
either by user action or by an error being reported by the server, then
all outstanding unacked messages are requeued for eventual delivery to
some other connection.

There are currently no timeouts involved: if you hold the Channel open,
you won't need to worry about anyone else being offered a message you're
working on.

Regards,
  Tony
-- 
 [][][] Tony Garnock-Jones     | Mob: +44 (0)7905 974 211
   [][] LShift Ltd             | Tel: +44 (0)20 7729 7060
 []  [] http://www.lshift.net/ | Email: tonyg at lshift.net