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<queue>
    <name>test</name>
    <test>
        <exchange>amq.direct</exchange>
        <priority>true</priority>
    </test>
</queue>

Client configuration/messaging model for priority queues

There are some other configuration & paradigm changes which are required in order that priority queues work as expected.

Set

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low pre-fetch

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Qpid clients receive buffered messages in batches, sized according to the pre-fetch value. The current default is 5000.

However, if you use the default value you will most likely probably not see desirable behaviour with messages of different priority. This is because a message arriving after the pre-fetch buffer has filled will not leap frog messages of lower priority. It will be delivered at the front of the next batch of buffered messages (if that is appropriate), but this is most likely NOT what you need.

So, you need to set the prefetch values for your client (consumer) to make this sensible. To do this set the system property XXXXXXXXXXXXXXXXXX before creating your consumer.

Setting the Qpid pre-fetch to 1 for your client means that message priority will be honoured by the Qpid broker as it dispatches messages to your client. (Coming soon: see JIRA).

There is a slight performance cost here if using the receive() method and you could test with a slightly higher pre-fetch (up to 10) if the trade-off between throughput and prioritisation is weighted towards the former for your application. (If you're using OnMessage() then this is not a concern.)

Single consumer per session