View source for OS/VS1

{{Short description|IBM operating system}}
{{Infobox OS
| name                   = OS/VS1<!-- Name of program or distribution -->
| logo                   = IBM logo.svg
| logo caption           = 
| logo size              = 120px
| logo alt               = 
| screenshot             = <!-- filename only (no wikilink, no Image:/File:) -->
| caption                = 
| screenshot_size        = 
| screenshot_alt         = 
| collapsible            = 
| version of             = <!-- For articles about releases of operating systems ONLY -->
| developer              = [[IBM]]<!-- Name of main developer or sponsor-->
| family                 = <!-- "Unix-like" or "Microsoft Windows" -->
| working state          = Historic<!-- "Current", "Discontinued" (operating systems), or "No longer supported" (releases) -->
| source model           = <!-- "Open source", "Closed source", or "Shared source" -->
| released               = 
| discontinued           = <!-- DON'T use this for articles about releases of operating systems -->
| RTM date               = <!-- {{Start date and age|YYYY|MM|DD|df=yes/no}} ONLY for articles about OS releases -->
| GA date                = <!-- {{Start date and age|YYYY|MM|DD|df=yes/no}} ONLY for articles about OS releases -->
| latest release version = OS/VS1 Basic Programming Extensions (BPE) Release 4
| latest release date    = {{Start date and age|1984|03}}
| latest preview version = 
| latest preview date    = <!-- {{Start date and age|YYYY|MM|DD|df=yes/no}} -->
| marketing target       = [[IBM mainframe]]s
| programmed in          = Assembler (XF), [[IBM PL/S|PL/S]] (nee BSL)
| language               = <!-- Supported human languages (English, French, Italian, Arabic, ...) -->
| update model           = <!-- APT, Windows Update, etc. -->
| package manager        = <!-- dpkg, rpm, Windows installer, etc. -->
| supported platforms    = [[System/370]]
| kernel type            = <!-- Hybrid, Monolithic, Microkernel, Exokernel, Nanokernel, etc. -->
| userland               = 
| ui                     = 
| license                = [[Proprietary software|Proprietary]]
| preceded by            = [[OS/360 and successors|OS/360]]
| website                = <!-- {{URL|www.example.org}} -->
| support status         = <!-- For articles about releases of operating systems ONLY -->
| other articles         = 
}}
{{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 [[OS/360 and successors#MFT|Multiprogramming with a Fixed number of Tasks (MFT)]] option of [[System/360]]'s operating system [[OS/360 and successors|OS/360]]. OS/VS1, in comparison to its predecessor, supported [[virtual memory]] (then called ''virtual storage''). OS/VS1 was generally available during the 1970s and 1980s, and it is no longer supported by IBM.

==Description==
OS/VS1 was OS/360 MFT II with a single virtual address space;  by comparison, [[OS/VS2 (SVS)|OS/VS2 SVS]] was [[OS/360 and successors#MVT|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.<ref>{{cite web |url=http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3148.html |title=System/370 Model 148" |website=IBM |archive-url=https://web.archive.org/web/20050311002817/http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3148.html |archive-date=2005-03-11 |url-status=dead}}</ref>

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.<ref>{{cite web |url=https://www.ibm.com/support/pages/history-cics-transaction-server |title=History of CICS Transaction Server |website=IBM|date=18 June 2024 }}</ref>

Installation and modification of OS/VS1 was accomplished via IBM's cumbersome [[System Generation (OS)|System Generation]] (SYSGEN) process.

==Remote Entry Services (RES)==
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. 

==IBM upgrades==
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 device|Direct Access Storage]], and for [[VM (operating system)|VM]] handshaking between [[VTAM]] and VM/VTAM Communications Network Application (VCNA).

IBM announced<ref>{{cite web
 |     title = OS/VS1 BASIC PROGRAMMING EXTENSIONS RELEASE 4 PLANNED FOR MARCH 1984 AVAILABILITY 5662-257
 |        id = 283-286
 |      date = September 15, 1983
 |       url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/6/897/ENUS283-286/index.html
 |      work = Announcement letters
 | publisher = IBM
 | archive-url = https://web.archive.org/web/20211210134820/https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/6/897/ENUS283-286/index.html
 | archive-date = 2021-12-10
 | url-status = dead
 }}
</ref> the last BPE release, OS/VS1 Basic Programming Extensions Release 4, on September 15, 1983, with planned general availability in March 1984.

IBM announced<ref>{{cite web
 |     title = OS/VS1 CONSOLIDATED STABILIZATION STATEMENT
 |        id = 284-086
 |      date = February 23, 1984
 |       url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/6/897/ENUS284-086/index.html
 |      work = Announcement letters
 | publisher = IBM
 | archive-url = https://web.archive.org/web/20211210134820/https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/6/897/ENUS284-086/index.html
 | archive-date = 2021-12-10
 | url-status = dead
 }}
</ref> 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{{snd}}[[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<ref>{{cite web
 |     title = IBM VM AND VSE-RELATED LICENSED PROGRAMS WITHDRAWAL FROM MARKETING AND DISCONTINUANCE OF PROGRAM SERVICES
 |        id = 289-016
 |      date = January 24, 1989
 |       url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/6/897/ENUS289-016/index.html
 |      work = Announcement letters
 | publisher = IBM
 | archive-url = https://web.archive.org/web/20211210134818/https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/6/897/ENUS289-016/index.html
 | archive-date = 2021-12-10
 | url-status = dead
 }}
</ref>  the intention to withdraw OS/VS1 and OS/VS1 BPE from marketing effective April 24, 1989, and to discontinue service effective February 28, 1990.

==Time-sharing==
Although IBM's [[Time Sharing Option]] (TSO) required VS2, customers with a 370/145 or 370/148 had other time-sharing options.<br>
One combination was VM/CMS for time sharing, and a guest "machine" running OS/360 MFT II for batch.<ref>During the 1970s, some universities ran the above combination during the day, and "went native" (no VM/CMS) at night, to run heavy batch work, e.g. administrative</ref>

===Conversational Remote Job Entry===
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.

===TONE for VS1===
A non-IBM time-sharing product named TONE (TSO-like, for VS1 / VS ONE)<ref>{{Cite magazine |url=https://books.google.com/books?id=-2ZtoSPs5IEC&pg=PA22 |title=Free Code Said to Manage IBM Control Block Usage |first=Don |last=Leavitt |magazine=Computerworld |volume=X |issue=49 |page=22 |date=1976-12-06 |publisher=IDG Enterprise |language=en |quote=The modification will be in the next version of the Tone III package and will be available at all Tone customer locations during the first quarter of 1977.}}</ref> was marketed by Tone Software Co.<ref>{{Cite magazine |url=https://books.google.com/books?id=LD44Qbu9AsUC&pg=PA72 |title=TONE III |type=Advertisement |magazine=Computerworld |volume=XI |issue=8 |page=72 |date=1977-02-21 |publisher=IDG Enterprise |language=en}}</ref>

==References==
{{Reflist}}

==Further reading==
*{{cite journal |title=Functional structure of IBM virtual storage operating systems, Part I: Influences of dynamic address translation on operating system technology |author1=M. A. Auslander |author1-link=Marc Auslander |author2=J. F. Jaffe |journal=IBM Systems Journal |date=1973 |volume=12 |issue=4 |pages=368-381 |doi=10.1147/sj.382.0340}}
*{{cite journal |url=http://bitsavers.org/pdf/ibm/370/OS_VS1/Wheeler_OS_VS1_Concepts_and_Philosophies_1974.pdf |title=OS/VS1 Concepts and Philosophies |author=T. F. Wheeler, Jr. |journal=IBM Systems Journal |date=1974 |volume=13 |issue=3 |pages=213–229 |doi=10.1147/sj.133.0213}}
*{{cite journal |title=The job entry subsystem of OS/VS1 |author1=J. H. Baily |author2=J. A. Howard |author3=T. J. Szczygielski |journal=IBM Systems Journal |date=1974 |volume=13 |issue=3 |pages=253–269 |doi=10.1147/sj.133.0253}} (The OS/VS1 job entry subsystem was named JES1)

{{IBM operating systems}}

{{DEFAULTSORT:OS VS1}}
[[Category:IBM mainframe operating systems]]
[[Category:1972 software]]