IBM GC34-5557-00 manual MQSeries Objects Queue Managers, Queues

MQSeries Objects

Queue Managers

A queue manager provides queuing services to applications, and manages the queues that belong to it. It ensures that:

vObject attributes are changed according to the commands received.

vSpecial events such as trigger events or instrumentation events are generated when the appropriate conditions are met.

vMessages are put on the correct queue, as requested by the application that makes the MQPUT call. The application is informed if this cannot be done, and an appropriate reason code is given.

Each queue belongs to a single queue manager and is said to be a local queue to that queue manager. The queue manager to which an application is connected is said to be the local queue manager for that application. For the application, the queues that belong to its local queue manager are local queues. A remote queue is simply a queue that belongs to another queue manager. A remote queue manager is any queue manager other than the local queue manager. A remote queue manager may exist on a remote machine across the network, or it may exist on the same machine as the local queue manager. MQSeries for AS/400, V5.1 supports multiple queue managers on the same machine.

Queues

A queue is an MQSeries object that can store messages. Each queue has queue attributes that determine what happens when applications reference the queue in MQI calls. The attributes indicate:

vWhether applications can retrieve messages from the queue (get enabled)

vWhether applications can put messages onto the queue (put enabled)

vWhether access to the queue is exclusive to one application or shared between applications

vThe maximum number of messages that can be stored on the queue at the same time (maximum queue depth)

vThe maximum size of messages that can be put on the queue (maximum message size)

4MQSeries for AS/400, V5.1 Quick Beginnings