What is a queue?

A queue is a data structure used to store messages.

Each queue is owned by a queue manager. The queue manager is responsible for maintaining the queues it owns, and for storing all the messages it receives onto the appropriate queues. The messages might be put on the queue by application programs, or by a queue manager as part of its normal operation.

WebSphere MQ Version 6.0 supports queues over 2 GB in size; Enabling large queues discusses this in more detail. For information about planning the amount of storage you need for queues, see the Quick Beginnings guide for your platform, or visit the WebSphere MQ Web site for platform-specific performance reports:

http://www.ibm.com/software/integration/ts/mqseries/

Predefined queues and dynamic queues

Queues can be characterized by the way they are created:

Retrieving messages from queues

Suitably authorized applications can retrieve messages from a queue according to the following retrieval algorithms:

The MQGET request from the application determines the method used.