[rabbitmq-discuss] Multiple subscription in the same thread

Fri Feb 13 09:58:34 GMT 2009

Roger,

On Thu, Feb 12, 2009 at 6:04 PM, Wilson, Roger <roger.wilson at lehman.com> wrote:
> A question to the wise.  Is it legal, advisable/risky or simply deviant
> to subscribe to multiple queues from the same Consumer?

>From a protocol perspective I would say that it shouldn't make a
difference. This is because the broker has knowledge of the existence
of any consumer, just the fact that it it can send deliveries to a
client with a particular tag so that the client can dispatch messages
accordingly.

> I have a java client implementing the Consumer interface which calls
> Channel.basicConsume on two queues, stays subscribed for about 10s and
> then calls basicCancel.
>
> This tends to work for a few calls and then when calling
> Channel.basicConsume for the second queue it hangs.  Always the second
> queue.
>
> Is there something fundamentally wrong with the same consumer consuming
> two queues?

Not really. The client will maintain two keys for the same consumer
reference, that's all. Maybe you can post some code that can reproduce
this behaviour.

Ben