dependent regions of IMS, IMS adapter, specified on EXEC parameter, SSM (subsystem member), IMS.PROCLIB library, BMP (batch message program), MPP (message processing program) connection control, message processing program (MPP)" /> Connecting from dependent regions

 

Connecting from dependent regions

The IMS adapter used in the control region is also loaded into dependent regions. A connection is made from each dependent region to WebSphere MQ. This connection is used to coordinate the commitment of WebSphere MQ and IMS work. To initialize and make the connection, IMS does the following:

  1. Reads the subsystem member (SSM) from IMS.PROCLIB.

    A subsystem member can be specified on the dependent region EXEC parameter. If it is not specified, the control region SSM is used. If the region is never likely to connect to WebSphere MQ, to avoid loading the adapter, specify a member with no entries.

  2. Loads the WebSphere MQ adapter.

    For a batch message program, the load is not done until the application issues its first messaging command. At that time, IMS tries to make the connection.

    For a message-processing program region or IMS fast-path region, the attempt is made when the region is initialized.