[rabbitmq-discuss] Topic routing

Wed Oct 22 17:19:32 BST 2008

On Oct 21, 2008, at 5:54 PM, Ben Hood wrote:

>>> Clustering will not affect the run time complexity of routing, since
>>> the routing table has to be coherent across the cluster.
>>>
>>> In a clustered scenario, the queues may reside on different nodes,
>>> whereas exchanges will *exist* on every node.
>
> What I meant to say that the parallelism does not change the
> fundamental complexity of the routing algorithm - sure it will
> distribute load, but O(n) is still O(n) even in a clustered context.
>
> So when you up the ante to the nth degree, you will find that this
> methodology *may* not cut it (although you are actually scaling
> linearly :-)
>
> The question remains - do you think that you will realistically take
> it to the nth degree.

Is "N" the number of subscriptions?  If so, I think we're fine, since  
my number of consumers will be relatively low.  If it's the number of  
topics, then that becomes a little more troublesome if I want to get  
clever with my routing keys to help distribute the consumption load  
across nodes.  (Troublesome, but not undoable)

Thanks,
Brian