docs/books/modules/user-guide/configuring-addresses-prioritized-message-delivery.adoc

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// This module is included in the following assemblies:
//
// configuring-address-space-message-routing.adoc

[id='configuring-addresses-prioritized-message-delivery-{context}']
= Configuring addresses for prioritized message delivery

You can set the priority level of an address to control how {RouterName} processes messages sent to that address. Within the scope of a connection, {RouterName} attempts to process messages based on their priority. For a connection with a large volume of messages in flight, this lowers the latency for higher-priority messages.

Assigning a high priority level to an address does not guarantee that messages sent to the address will be delivered before messages sent to lower-priority addresses. However, higher-priority messages will travel more quickly through the router network than they otherwise would.

[NOTE]
====
You can also control the priority level of individual messages by setting the priority level in the message header. However, the address priority takes precedence: if you send a prioritized message to an address with a different priority level, the router will use the address priority level.
====

.Procedure

* In the `{RouterConfigFile}` configuration file, add or edit an address and assign a priority level.
+
--
This example adds an address with the highest priority level. The router will attempt to deliver messages sent to this address before messages with lower priority levels.

[options="nowrap",subs="+quotes"]
----
address {
    prefix: my-high-priority-address
    priority: 9
    ...
}
----
`priority`:: The priority level to assign to all messages sent to this address. The range of valid priority levels is 0-9, in which the higher the number, the higher the priority. The default is 4.
--

.Additional resources

* For more information about setting the priority level in a message, see the {AmqpSpecLink}.