Comment 9 for bug 1676586

As a workaround, the charm could configure a TTL policy for the queue. That way the queue would at least not grow indefinitely.
Or even better perhaps use max-length. https://www.rabbitmq.com/maxlength.html

rabbitmqctl set_policy ceilometer-overflow metering.sample '{"max-length":20000}' --apply-to queues