Requirements for programs that use RRSAF

The Resource Recovery Services attachment facility (RRSAF) enables programs to communicate with Db2. Before you invoke RRSAF in your program, ensure that your program satisfies any requirements for using RRSAF.

When you write programs that use RRSAF, ensure that they meet the following requirements:
  • The program accounts for the size of the RRSAF code. The RRSAF code requires about 10 KB of virtual storage per address space and an additional 10 KB for each TCB that uses RRSAF.
  • If your local environment intercepts and replaces the z/OS® LOAD SVC that RRSAF uses, you must ensure that your version of LOAD manages the load list element (LLE) and contents directory entry (CDE) chains like the standard z/OS LOAD macro. RRSAF uses z/OS SVC LOAD to load a module as part of the initialization after your first service request. The module is loaded into fetch-protected storage that has the job-step protection key.

You can prepare application programs to run in RRSAF similar to how you prepare applications to run in other environments, such as CICS®, IMS, and TSO. You can prepare an RRSAF application either in the batch environment or by using the Db2 program preparation process. You can use the program preparation system either through DB2I or through the DSNH CLIST.