Meaning – The term MVS, or multiple virtual storages, refers to the most commonly used operating system on the System/370 and System/390 IBM mainframe computers. IBM developed MVS, along with OS/VS1 and SVS, as a successor to OS/360.
At first, IBM described MVS as simply a new release of OS/VS2, but it was, in fact, a major rewrite. OS/VS2 Release 1 was an upgrade of OS/360 MVT that retained most of the original code and, like MVT, was mainly written in assembly language. The MVS core was almost entirely written in Assembler XF, although a few modules were written in PL/S, but not the performance-sensitive ones, in particular not the Input/Output Supervisor (IOS).
Example of usage – “MVS maximized processing potential by providing multiprogramming and multiprocessing capabilities. Like its MVT and OS/VS2 SVS predecessors, MVS supported multiprogramming; program instructions and associated data are scheduled by a control program and given processing cycles.”