[rabbitmq-discuss] Consumers stopped consuming messages

Tue Jul 20 10:26:32 BST 2010

On 20/07/10 09:55, Florence Chabanois wrote:
<snip>
> We noticed that /*sometimes*/, consumers hang (well, they are not
> blocked, but they dont consume messages anymore). We can see that
> because each consumer save around 100 msg/sec in database, so when one
> is stopping consumming, the overall messages saved per seconds in DB
> fall down with the same ratio (if let say 3 consumers stop, we fall
> around 600 msg/sec to 300 msg/sec).
<snip>
> FYI there has been a similar issue here, but it wasn't resolved :
> http://old.nabble.com/Consumer-stop-to-receive-messages-but-continue-listening-queue-problem.-td27872888.html

Hi Florence. One possibility that was considered in the linked thread 
was that all the messages were being sent to some consumers due to 
basic.qos not being set (in the absence of basic.qos, Rabbit is allowed 
to do that).

So:

* Are you setting the basic.qos prefetch count?
* What does rabbitmqctl lists_queues say about he queue when the system 
is in this state?
* Are you able to post your spike code anywhere?

Cheers, Simon

-- 
Simon MacMullen
Staff Engineer, RabbitMQ
SpringSource, a division of VMware