19.3. Delivery Count Persistence

In normal use, HornetQ does not persist an updated delivery count until a message is rolled back (that is, the delivery count is not updated before the message is delivered to the consumer). In most messaging use cases, the messages are consumed, acknowledged and forgotten as soon as they are consumed. In these cases, updating the delivery count persistently before delivering the message would add an extra persistent step for each message delivered, imposing a significant performance penalty.

However, if the delivery count is not updated persistently before message delivery, in the event of a server crash, the delivery of some messages may not be reflected in the delivery count. Therefore, during the recovery phase, the server may deliver the message with redelivered set to false when it should be true.

Since this behavior breaks strict JMS semantics, delivery count can be persisted before message delivery in HornetQ. However, this is disabled by default for performance reasons. To enable this behavior, set persist-delivery-count-before-delivery to true in <JBOSS_HOME>/jboss-as/server/<PROFILE>/deploy/hornetq/hornetq-configuration.xml:

<persist-delivery-count-before-delivery>
  true
</persist-delivery-count-before-delivery>

<persist-delivery-count-before-delivery>
  true
</persist-delivery-count-before-delivery>