[rabbitmq-discuss] Miscellaneous Question

Wed Jan 14 23:11:36 GMT 2009

Jason,

Jason J. W. Williams wrote:
> * How does one monitor memory consumption by a queue?

rabbitmqctl list_queues name memory

> * If messages persist to disk do they relieve memory pressure on the queue?

No. This has been discussed at some length on the list and there are 
several

> * How resilient is the Mnesia DB to sudden death of the process using it?

It should be quite resilient. See
   http://www.erlang.org/doc/apps/mnesia/Mnesia_chap7.html
in particular sections 6.6 to 6.9 for some more details on what happens 
on startup, how various failure scenarios are dealt with etc.

> Clearing the Mnesia files in /var/lib/rabbitmq
> allowed Rabbit to start...but I assume in a production scenario this
> would have eliminated any durable queues/exchanges and persistent
> messages.

Right. Though note that persisted messages aren't stored in mnesia; it 
just so happens that we decided to store them in files in the same 
directory as mnesia.

Matthias.