RACF® can use VLF to cache signature verification data in order to improve the performance of signature verification of signed program objects. This in turn can improve the load time of signed program objects. This is a consideration only for installations that choose to exploit signature verification.

For background information, see Program signing and signature verification. For implementation details, see "Enabling RACF to verify signed programs" in z/OS Security Server RACF Security Administrator's Guidez/OS Security Server RACF Security Administrator's Guide.