[rabbitmq-discuss] Protection against slow consumers

Mon Nov 1 16:33:23 GMT 2010

Hi Emile

> I assume you have subscribers each set up with their own queue and binding.

Yes, each subscriber uses an exclusive auto-delete queue bound to the  
exchange.

> In this case I would expect long queues associated with slow  
> subscribers to be persisted to disk automatically. This prevents RAM  
> pressure, which the broker attempts to relieve by blocking producers.

I see what you mean, but what if the subscriber uses a large prefetch  
buffer and consumes without ever acking?

Also, even if long queues get persisted to disk, this consumes  
resources and the queues can't grow forever.

Is there no way how can we limit the queue size or message time to live?

> This assumes that you are running version 2.0.0 or later.

We are running RabbitMQ 2.1.0.

Cheers
Jiri