System-Managed Storage

In early 1988, IBM announced the Data Facility Storage Management Subsystem (DFSMS™), comprising functions in MVS/DFP™, other products in the Data Facility family, and RACF. This announcement constituted a major step in the realization of system-managed storage. The need for system-managed storage was established in the late 1970s and early 1980s, through growing customer requirements in the management of external storage space, performance, availability, and device installability within and across systems in these customers' installations. The concept of system-managed storage is an evolutionary one, culminating in a resource manager for external storage that separates the logical view of data from physical device characteristics, simplifies interfaces for the use and administration of storage, integrates the functions of storage management products, and provides a synergy of hardware and software functions to effect complex-wide management of external storage resources, as discussed in this paper.