MAI Installation Exit MAIEX02 › How You Implement the MAI Exit › Exit Serialization › First-level Serialization

First-level Serialization

The first level of serialization uses MAIEX02S=SYSTEM. This setting is the default and ensures that calls to the exit are serialized. In the previous example, the Session End call would not be made until the Session Start call had completed. This level is used where, for instance, the exit is maintaining a control block structure or where the various calls update the System Correlator. It ensures that a System Correlator set by one call is always passed to the next call.

The only drawback with this level of serialization is that the starting and ending of MAI sessions is single-threaded so that only one can proceed at a time. However, because the path through MAIEX02 is usually short and fast, this drawback is not a problem.