MVS/370

MVS/370 is the earliest currently supported version of the MVS operating system. The MVS/370 operating system architecture is based on a 24-bit address. Because of this 24-bit address length, programs running under MVS/370 are each given 16 megabytes of contiguous storage. MVS/370 maximizes processing potential by proving multiprogramming and multiprocessing capabilities.

Like its MVT predecessor, MVS/370 supported multiprogramming; program instruction and associated data are transferred to a control program and given processing cycles. Unlike a single-programming operating system, MVS/370 maximizes the use of the processing potential by dividing processing cycles among the instruction associated with several different concurrently running programs. This way, the control program does not have to wait for the I/O operation to complete before proceeding. By executing the instructions for multiple programs, the computer is able to switch back and forth between active and inactive programs.

MVS/370 also gave users the opportunity to network together two or more data processing systems. This capability became known as multiprocessing.fact|date=November 2007 Multiprocessing systems are either loosely coupled, which means that each computer has access to a common workload, or tightly coupled, which means that the computers share the same real storage and are controlled by a single copy of the operating system.huh|date=November 2007 Because multiprocessing system can execute instructions simultaneously, they offer greaterhuh|date=November 2007 processing power than single-processing system. As a result, MVS/370 was able to address the business problems brought on by the need to process large amounts of data.