[rabbitmq-discuss] 2 nodes, 4k queues

Thu Nov 19 07:27:24 GMT 2009

Hi,

We had a case of a 2 nodes cluster where message delivery latency was
unacceptably slow (~ 1-2 min) when the number of queues rose above 4k.
All the messages were going out to a single topic exchange, average
message size is 5KB, the number of messages was not more than 10/s and
most of the messages matched 3-4 queues. We're using topic matching
between exchange and queues. RabbitMQ was running at about 20-30% CPU on
large EC2 instances, and about 9% memory, so there doesn't seem to be a
memory or CPU bottleneck on the machines. Is this kind of performance
expected (and if it is, how many queues per node would you suggest), or 
have we hit a configuration problem? Any ideas on monitoring/measuring 
what starts slowing down processing when the number
of queues goes up.

--
gojko adzic
http://gojko.net