Once you have installed and verified ISPF, you can enhance its performance by adding the LPA-eligible load modules (in the SISPLPA library) to the LPA list in an LPALSTxx member of PARMLIB. Add those load modules not eligible for LPA (that is, those in the SISPLOAD library that are not re-entrant) to the link list in an LNKLSTxx member of PARMLIB. For information about adding data sets to the Link and LPA lists, see z/OS MVS Initialization and Tuning Reference. You can then remove these data sets from the STEPLIB in your TSO LOGON procedure. After adding SISPLPA to LPALST and SISPLOAD to LNKLST, specify CLPA as an initial program load (IPL) parameter to force the SISPLPA modules into the link pack area and to have SISPLOAD added as a system link library.

ISPF performance directly relates to the number of load modules that reside in the pageable LPA because these modules are not loaded into the user's private storage when they are called. For optimum performance, all of the eligible ISPF licensed program load modules should be in the LPA. However, to load all eligible modules to the LPA, your system would need a very large LPA.

Any module that is re-entrant (that is, has the RN attribute) is eligible for the LPA.

No modules are required in the LPA. Table 1 lists the load modules recommended for inclusion in the LPA.

To conserve LPA space:

• Move some of the infrequently used modules to a system-link library. Keep the modules you most frequently use in the LPA.
• If you are not using SCLM, move all load modules that begin with FLM from the SISPLPA library to the SISPLOAD library so that they are in a system link library instead of the Link-Pack area.