Message priority

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

Message priority

The order in which messages are sent to a queue on the destination computer, their priority, is determined first by the queue priority (also known as the base priority), and then by the message priority. The queue priority for public queues listed in Active Directory can be set to any number from -32768 to 32767. The default queue priority is 0.

Message priority affects how Message Queuing handles the message while it is in route, as well as where the message is placed in the queue. Higher priority messages are given preference during routing, and inserted toward the front of the queue. Message Queuing applications can set the message priority for nontransactional messages in the range from 0 to 7, where 7 represents the highest priority. The default value is 3. Messages with the same priority are placed in the queue according to their arrival time. Message Queuing automatically sets the priority level of transactional messages to 0.

Messages are sent to public queues based on the sum of the destination queue's priority and each message's priority. Messages with the highest resultant priority value are sent first.

Private queues do not support queue priority. Messages are sent to private queues based only on message priority.