[rabbitmq-discuss] Confirm if the message was published

Mon Jul 15 09:54:31 BST 2013

On 11/07/13 14:03, Guilherme Labigalini wrote:
> Looks like RabbitMQ needs more time to confirm/write messages to disk
> when the queue size is big (like 2GB).

Not necessarily, but in general you shouldn't make any assumptions about 
the timeliness of confirms. There is a lot batching and other 
optimisations going on at the server which improve overall throughput 
but result in highly variable confirm latencies.

> There is any recommendation about how much data I can "store" the
> message queues?

On a 64-bit machine, about 7 million messages per gigabyte of memory 
rabbit is configured to use (i.e. based on the vm_memory_high_watermark 
setting). Plus of course you need disk space for all the payloads + a 
few hundred bytes of overhead, times two (due to the way disk space gets 
reclaimed, there can be up to 50% "garbage").

Regards,

Matthias