[rabbitmq-discuss] Consumer setup performance / starvation issue

[Matthias Radestock]

Etrik,

On 20/06/11 19:25, flzz wrote:
> 1. Start a single producer, let it queue 500,000 messages or so, then
> stop it
> 2. Start up 16 workers to consume the queue (workers have a prefetch
> of 1)
>
> The first 7 to 8 workers will successfully setup and start
> processing messages, the other 8 to 9 workers will sit in a wait
> state while trying to set themselves up as consumers. Only after all
> the messages in the queue are processed will the rest of the workers
> successfully establish a connection as a consumer. >
> [...]
> Another item worth mentioning, is that rabbitmqctl list_channels
> will exhibit the same wait issue when workers are processing the
> queued messages.

I have a theory for why this may be happening. To confirm it, could you 
please get your workers to run more slowly, e.g. insert a sleep/pause 
between them receiving a message and then ack'ing it. Does that change 
the behaviour?

Regards,

Matthias.