New Destination Metrics

Message Queue 4.2 includes new destination metrics that can be useful in monitoring destinations in a broker cluster. In a broker cluster, destinations are propagated to all brokers in the cluster. However, a message, when produced, is stored in the target destination of the message producer's home broker, and is sent to the corresponding destination on another broker in the cluster only if there is an active consumer for that destination. As a result, the messages stored in a specified destination depends on the broker in the cluster on which the specified destination resides.

Put another way, in a broker cluster, the messages stored in a given destination on a given broker in the cluster, consist of messages produced directly to the destination as well as messages sent to the destination from remote brokers in the cluster. In analyzing message routing and delivery in a broker cluster, it is sometimes helpful to know how many messages in a destination are local (locally produced) and how many are remote (remotely produced).

The following table shows two new physical destination metric quantities included in Message Queue 4.2. The new metric quantities are available through the imqcmd list dst and imqcmd query dst commands and through new JMX attributes (see Destination Monitor MBean.