(Multiple Virtual Storage) Introduced in 1974, the primary operating system used with IBM mainframes (the others are VM and DOS/VSE). MVS is a batch processing-oriented operating system that manages large amounts of memory and disk space. Online operations are provided with CICS, TSO and other system software. MVS/Extended Architecture MVS/XA manages the enhancements introduced in 1981 with IBM's 370/XA architecture, including 2GB of virtual memory. MVS/Enterprise Systems Architecture MVS/ESA manages the enhancements made to large scale mainframes, including 16TB of virtual memory, introduced in 1988 with IBM's ESA/370 architecture. MVS/ESA ran on all models of the System/390 ES/9000 product line introduced in 1990. OS/390 In 1996, MVS/ESA was packaged with an extensive set of utilities that was renamed OS/390. The name MVS was still used to refer to the base control program in OS/390. See OS/390.