This topic provides a brief overview of installation-written exits. z/OS MVS Installation Exits describes the SMF installation and Using the SMF Dump Programs describes the SMF dump program exits.
You can customize SMF to meet your installation's requirements by coding installation exit routines or by writing application programs that use SMF macros.
SMF provides exits in the control program that allow installations to add installation-written routines to the control program to perform additional processing. Installation-written routines at SMF exits receive control at different times as a job moves through the system. They receive control when specific events occur, such as when a job CPU-time limit expires. These installation-written routines could collect additional information, cancel jobs, or enforce installation standards.
The IEFUJV, IEFUJP, and IEFU85 exits must run in 31-bit addressing mode. All other exits can execute in either 24-bit or 31-bit addressing mode. IBM® recommends that you use 31-bit addressing mode whenever possible.
Exit routines that access SMF records with sub-sections, such as record type 30, should be coded using triplets (offset to xxx section, number of xxx sections, length of xxx section) rather than coding the exit to access the fields directly. An installation can use the triplets to calculate the location of each field, and avoid the need to recompile the exit with the mapping macro each time a field is added to the end of a section. When the position of a field changes, the exit will locate the field relative to the beginning of the section in which it is contained.
A brief description of the IBM-supplied exits is included here. z/OS MVS Installation Exits describes the SMF installation exits and how to code and use them. Table 1 describes the SMF dump program exits.