Introduction › Distributed Processing Concepts and Terminology › Synchronous vs. Asynchronous Processing › Synchronous Cooperative Flows

Synchronous Cooperative Flows

For synchronous cooperative flows, the client application blocks execution until the outstanding response is received. This blocking behavior prevents the requesting application from engaging in any processing that is concurrent to the execution of an outstanding cooperative flow request.

Using synchronous cooperative flows causes a DPC to serialize its processing when it has to flow to other target procedures. Processing within the DPC cannot continue until control is returned to the DPC from a previously executed cooperative flow.

Within a CA Gen model a synchronous cooperative flow is generated when using the following types:

• A link type Dialog Flow in a Window Manager to flow to a target PStep that is packaged in a Server Manager
• A Procedure Step USE (PStep USE) action language statement, where the target PStep is packaged in a Server Manager

The following illustration depicts a DPC that contains three synchronous cooperative flows. The processing within the DPC suspends its execution until the target Procedure Step returns control to the DPC. The synchronous cooperative flow behaves as a Remote Procedure Call (RPC).

A user-written client application that uses a proxy can perform a synchronous cooperative flow to a DPS by using the execute mechanism that is exposed in the proxy that is associated with the target PStep.