The role of CQS in a shared-queues environment

The Common Queue Server (CQS) is a generalized server that manages objects on a coupling facility list structure, such as a queue structure or a resource structure. CQS receives, maintains, and distributes data objects from shared queues on behalf of multiple clients.

Each client communicates with a CQS to access the shared queues. IMS is one example of a CQS client that uses CQS to manage both its shared queues and shared resources.

CQS uses the z/OS® coupling facility as a repository for data objects. Storage in a coupling facility is divided into distinct objects called structures. Authorized programs use structures to implement data sharing and high-speed serialization. The coupling facility stores and arranges the data according to list structures. Queue structures contain collections of data objects that share the same name, known as queues.