Interface Subtask Management

Each WST handles requests for CICS® users through the CST. One WST communicates with only one DTF, but multiple WSTs can communicate with one DTF. The DTF-connected WSTs are not associated with any particular CICS transactions. The various IBM® Connect:Direct® requests generated by CICS Interface users are handled by any of the multiple WSTs which are for a particular DTF node. The CST oversees all the WSTs, and is responsible for coordinating work generated by CICS transactions.

One WST is attached per node at the CICS Interface startup, as defined in the CONFIGURATION file. Additional WSTs for a node are attached as needed, based on concurrent CICS Interface user demand. The maximum number of WSTs (tasks) attached globally for the interface and per DTF node is defined with CONFIGURATION control and DTF node parameters. The DTF node connection limit is edited to be no larger than the number of CICS interactive applications specified in the Network Map for that node.

When an attached WST becomes inactive (is not used for any requests) for a period of time, it is detached by CST. The inactive interval is defined with a CONFIGURATION control option. You can suppress WST activation by DTF node with a CONFIGURATION DTF node parameter.