![]() | |
Developer | IBM |
---|---|
Written in | Assembler (XF), PL/S (nee BSL) |
Working state | Historic |
Latest release | OS/VS1 Basic Programming Extensions (BPE) Release 4 / March 1984 |
Marketing target | IBM mainframes |
Platforms | System/370 |
License | Proprietary |
Preceded by | OS/360 |
History of IBM mainframe operating systems |
---|
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 (then called virtual storage). [1] OS/VS1 was generally available during the 1970s and 1980s, and it is no longer supported by IBM.
OS/VS1 was OS/360 MFT II with a single virtual address space; by comparison, OS/VS2 SVS was OS/360 MVT with a single virtual address space. OS/VS1 was often installed on mid-range IBM mainframe systems, such as the System/370 Model 145 and, later, the System/370 Model 148. [2]
OS/VS1 was intended to manage a medium-sized work load (for the 1970s) consisting only of batch processing applications, running within a fixed number of operating system partitions via the batch job management system Job Entry Subsystem 1 (JES1). This was in contrast to OS/VS2 which was intended to handle larger work loads consisting of batch applications, online interactive users (using the Time Sharing Option, or TSO), or a combination of both. However, OS/VS1 could, and often did, support interactive applications and users by running IBM's CICS transaction processing monitor as a job within one of its partitions. [3]
Installation and modification of OS/VS1 was accomplished via IBM's cumbersome System Generation (SYSGEN) process.
OS/VS1 included a replacement for OS/360 RJE. It allowed submission and retrieval of jobs by 2770, 2780 and 3780 terminals and by workstation programs included with OS/VS1 for, e.g., 1130. RES included Remote Terminal Access Method and a closer integration with Job Management than what RJE had.
OS/VS1 went through seven product releases. IBM enhanced OS/VS1 Release 7 with four releases of the IBM OS/VS1 Basic Programming Extensions (BPE), product 5662-257. BPE provides support for new 1980s hardware, such as 3380 Direct Access Storage, and for VM handshaking between VTAM and VM/VTAM Communications Network Application (VCNA).
IBM announced [4] the last BPE release, OS/VS1 Basic Programming Extensions Release 4, on September 15, 1983, with planned general availability in March 1984.
IBM announced [5] the end of functional enhancements to OS/VS1 in 1984. IBM recommended OS/VS1 installations migrate to MVS/370 or MVS/XA. To assist with the migration to MVS/XA, IBM made the VM/XA Migration Aid. It allowed installations to run OS/VS1 and MVS/XA simultaneously on the same machine, as guests of a third system – VM/XA. This way, the new MVS/XA system could be tested while the old production OS/VS1 system was still in use.
On January 24, 1989, IBM announced [6] the intention to withdraw OS/VS1 and OS/VS1 BPE from marketing effective April 24, 1989, and to discontinue service effective February 28, 1990.
Although IBM's Time Sharing Option (TSO) required VS2, customers with a 370/145 or 370/148 had other time-sharing options.
One combination was VM/CMS for time sharing, and a guest "machine" running OS/360 MFT II for batch. [7]
Optional component of OS/360 MFT II, OS/360 MVT and OS/VS1, CRJE allowed the user at a line-mode terminal to edit text datasets, submit jobs and access job output.
A non-IBM time-sharing product named TONE (TSO-like, for VS1 / VS ONE) [8] was marketed by Tone Software Co. [9]
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.
OS/390 is an IBM operating system for the System/390 IBM mainframe computers.
Computer operating systems (OSes) provide a set of functions needed and used by most application programs on a computer, and the links needed to control and synchronize computer hardware. On the first computers, with no operating system, every program needed the full hardware specification to run correctly and perform standard tasks, and its own drivers for peripheral devices like printers and punched paper card readers. The growing complexity of hardware and application programs eventually made operating systems a necessity for everyday use.
The IBM System/370 (S/370) is a model range of IBM mainframe computers announced on June 30, 1970, as the successors to the System/360 family. The series mostly maintains backward compatibility with the S/360, allowing an easy migration path for customers; this, plus improved performance, were the dominant themes of the product announcement. In September 1990, the System/370 line was replaced with the System/390.
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.
VM is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers.
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.
Conversational Programming System or CPS was an early Time-sharing system offered by IBM which ran on System/360 mainframes circa 1967 through 1972 in a partition of OS/360 Release 17 MFT II or MVT or above. CPS was implemented as an interpreter, and users could select either a rudimentary form of BASIC or a reasonably complete version of PL/I. A third option provided remote job entry (RJE) features allowing users to submit JCL job streams for batch processing. A fourth option was called control mode. Normally, only the system operator would be permitted to use control mode. The available features in control mode included:
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 IBM mainframe operating systems is significant within the history of mainframe operating systems, because of IBM's long-standing position as the world's largest hardware supplier of mainframe computers. IBM mainframes run operating systems supplied by IBM and by third parties.
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.
Group Control System (GCS) is an operating system made by IBM, meant to run as a guest of VM. GCS is an integral component of the discontinued VM/SP, VM/XA SP, VM/ESA and current z/VM IBM System product offerings.
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):
Data Facility Storage Management Subsystem (DFSMS) is a central component of IBM's flagship operating system z/OS. It includes access methods, utilities and program management functions. Data Facility Storage Management Subsystem is also a collective name for a collection of several products, all but two of which are included in the DFSMS/MVS product.
The term IBM platform could refer to any of the hardware and operating systems below.