[rabbitmq-discuss] RabbitMQ message receiving slower than publishing

[Matthew Sackman]

On Wed, Nov 03, 2010 at 05:15:55PM +0000, T-zex wrote:
> We are running the latest version of RabbitMQ 2.1.1 on windows server,
> and using .Net client. We are running a test as follows: publishing
> 500000 messages to the transcient non durable fanout exchange, the
> client uses autodelete queue. There is only one queue. Publisher sends
> ~ 10K messages per second. After all messages are sent it disconnects.
> rabbitmqctl tool is showing that queue size is 0, but receiver is
> still getting messages for a few seconds, it has received only 60% of
> messages. Do you know why there is such a delay and how to minimize
> it?

Receiver has no qos set and is using basic.consume? As a result, the
broker has sent all messages to the receiver (thus the queue is empty),
but the receiver has not processed them all yet.

Assuming the receiver is acknowledging messages (noAck = false), if you
watch the number of unacknowledged messages in the queue, you should see
that drop as the receiver churns through its backlog.

...is my guess.

Matthew