Operating System/Virtual Storage 2 (OS/VS2) is the successor operating system to OS/360 MVT in the OS/360 family.
IBM mainframes are large computer systems produced by IBM since 1952. During the 1960s and 1970s, IBM dominated the large computer market. Current mainframe computers in IBM's line of business computers are developments of the basic design of the IBM System/360.
Multiple Virtual Storage, more commonly called MVS, was 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. It is unrelated to IBM's other mainframe operating system lines, e.g., VSE, VM, TPF.
In computing, virtual memory, or virtual storage is a memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" which "creates the illusion to users of a very large (main) memory".
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single process might be underway at any time.
Time Sharing Option (TSO) is an interactive time-sharing environment for IBM mainframe operating systems, including OS/360 MVT, OS/VS2 (SVS), MVS, OS/390, and z/OS.
This article presents a timeline of events in the history of computer operating systems from 1951 to the current day. For a narrative explaining the overall developments, see the History of operating systems.
Job Control Language (JCL) is a name for scripting languages used on IBM mainframe operating systems to instruct the system on how to run a batch job or start a subsystem.
In computing, spooling is a specialized form of multi-programming for the purpose of copying data between different devices. In contemporary systems, it is usually used for mediating between a computer application and a slow peripheral, such as a printer. Spooling allows programs to "hand off" work to be done by the peripheral and then proceed to other tasks, or to not begin until input has been transcribed. A dedicated program, the spooler, maintains an orderly sequence of jobs for the peripheral and feeds it data at its own rate. Conversely, for slow input peripherals, such as a card reader, a spooler can maintain a sequence of computational jobs waiting for data, starting each job when all of the relevant input is available; see batch processing. The spool itself refers to the sequence of jobs, or the storage area where they are held. In many cases, the spooler is able to drive devices at their full rated speed with minimal impact on other processing.
Disk Operating System/360, also DOS/360, or simply DOS, is the discontinued first member of a sequence of operating systems for IBM System/360, System/370 and later mainframes. It was announced by IBM on the last day of 1964, and it was first delivered in June 1966. In its time, DOS/360 was the most widely used operating system in the world.
The Job Entry Subsystem (JES) is a component of IBM's MVS mainframe operating systems that is responsible for managing batch workloads. In modern times, there are two distinct implementations of the Job Entry System called JES2 and JES3. They are designed to provide efficient execution of batch jobs.
Remote job entry is the procedure for sending requests for non-interactive data processing tasks (jobs) to mainframe computers from remote workstations, and by extension the process of receiving the output from such jobs at a remote workstation.
Operating System/Virtual Storage 1, or OS/VS1, is a discontinued IBM mainframe computer operating system designed to be run on IBM System/370 hardware. It was the successor to the Multiprogramming with a Fixed number of Tasks (MFT) option of System/360's operating system OS/360. OS/VS1, in comparison to its predecessor, supported virtual memory. OS/VS1 was generally available during the 1970s and 1980s, and it is no longer supported by IBM.
A Supervisor Call instruction (SVC) is a hardware instruction used by the System/360 family of IBM mainframe computers up to contemporary zSeries, the Amdahl 470V/5, 470V/6, 470V/7, 470V/8, 580, 5880, 5990M, and 5990A, and others; Univac 90/60, 90/70 and 90/80, and possibly others; the Fujitsu M180 (UP) and M200 (MP), and others; and is also used in the Hercules open source mainframe emulation software. It causes an interrupt to request a service from the operating system. The system routine providing the service is called an SVC routine. SVC is a system call.
The history of operating systems running on IBM mainframes is a notable chapter of history of mainframe operating systems, because of IBM's long-standing position as the world's largest hardware supplier of mainframe computers.
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB and Input/Output Control System (IOCS) packages for the IBM 7090/7094 and even more so by the PR155 Operating System for the IBM 1410/7010 processors. It was one of the earliest operating systems to require the computer hardware to include at least one direct access storage device.
System Generation (SysGen) is a two-stage process for installing or updating OS/360, OS/VS1, OS/VS2 (SVS), OS/VS2 (MVS) and chargeable systems derived from them. There are similar processes for, e.g., DOS/360, which this article does not cover. Also, some of the details have changed between releases of OS/360 and many details do not carry over to later systems.
Single Virtual Storage (SVS) refers to Release 1 of Operating System/Virtual Storage 2 (OS/VS2); it is the successor system to the MVT option of Operating System/360. OS/VS2 (SVS) was a stopgap measure pending the availability of MVS, although IBM provided support and enhancements to SVS long after shipping MVS.
OS/VS may refer to one of a number of IBM operating systems for System/370 and successors characterized by the use of virtual storage (VS):
The term IBM platform could refer to any of the hardware and operating systems below.