For Queues, that's right - all messages are stored until consumed (once and only once consumption).
For Topics, it's a little more complicated. It's easiest to think of it this way: topics never store messages themselves; topic subscriptions may store messages. Durable subscriptions do store messages for the obvious reason (need to deliver to the durable subscriber across broker restarts). And, since the only messages that go to a subscription are those that match its selector, those would be the only ones stored. With that said, durable subscriptions tend to lead to many problems, so please use them with care. Any part of the system that relies on a very specific consumer being active can easily run into slow consumption problems. Selectors with Queues also tend to be similarly problematic when messages that do not match any consumer's selector are sitting around (they also perform poorly with large numbers of consumers because they are evaluated in order against every consumer until a match is found). Camel is a good tool for handling patterns in which selectors are desirable. -- View this message in context: http://activemq.2283324.n4.nabble.com/Persistent-message-and-selectors-tp4689542p4689581.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.
