Enclave initialization

The storage tuning user exit is called after the assembler user exit is called for enclave initialization. At this point the storage tuning user exit is passed information about the main program, a user word, and an area to provide Language Environment storage option values.

When running on non-CICS or on CICS® without automatic storage tuning, the storage tuning user exit can do one or both of the following:

Provide Language Environment storage option values. The storage option values for each program that needs to be tuned could be in a file or in an incore table. The address of an incore table could be stored in the user word. The storage tuning user exit could look up the storage values for the program and pass them back to Language Environment.
Request that Language Environment collect storage tuning information. By requesting storage tuning information, it will cause Language Environment to collect storage tuning information and then call the storage tuning user exit when the enclave terminates.

When running on CICS with automatic storage tuning, the storage tuning user exit has limited function. At the enclave initialization call, any storage option values provided are ignored. If the storage tuning user exit wants to provide storage option values, it has to provide them at the new load module call and at the enclave termination call. The storage tuning user exit can turn off the request by automatic storage tuning to collect storage allocation information.