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When using ceilometer we set up all our services to send notifications.

Ceilometer consumes these messages but we still end up with the notification.X queues filling up.

Is this because ceilometer re-queues the messages or are the notifications left not something that ceilometer cares about?

Guess I'm just wondering what is the expected behaviour. Currently I have to keep manually purging the notification queues in rabbit admin. 
I was expecting ceilometer to consume these messages.

Cheers,
Sam