[rabbitmq-discuss] 2 nodes, 4k queues

Fri Nov 20 22:05:24 GMT 2009

> Yeah, our topic matching is inefficient - it's O(n) where n is the
> number of bindings. We do have a bug open to improve this. You didn't
> mention the number of bindings that you have, but if you're up to 20k
> bindings or so then I wouldn't be surprised if this is the performance
> you're getting. In general, until we fix this bug (it should become
> O(log₂(n)) because really it should just be walking a tree), we'd
> probably recommend to use a direct or fanout exchange and then drop
> inappropriate messages in the consumer. I know this isn't ideal, but it
> might solve the problems you're seeing.

Is it O(n) relative to the number of bindings per exchange, or per server node, or per cluster? I'm researching the overhead of a lot of bindings as well... Does the lookup overhead increase in a cluster, or is the 'route table' replicated to all nodes so it's always an in-memory lookup?

-JD