As an alternative to maintaining all RACF® profiles of your primary RACF database in a single MVS™ data set, RACF allows you to have up to 90 primary data sets, and an equal number of associated backup data sets. You should consider using multiple RACF data sets to reduce device contention and to reduce the number of resources that are made unavailable by the loss of one data set or device (although for installations running in data sharing mode, a single data set might provide satisfactory performance). The best number of RACF data sets for your installation depends on the extent to which you use RACF.

For more information about creating multiple RACF data sets, see "RACF database split/merge/extend utility program (IRRUT400)" in z/OS Security Server RACF System Programmer's Guide.