Berkeley Timesharing System
Encyclopedia
The Berkeley Timesharing System was a pioneering time-sharing
operating system
implemented between 1964 and 1967 at the University of California, Berkeley
. It was designed as part of Project Genie
and marketed by Scientific Data Systems
for the SDS 940
computer system.
It was the first commercial time-sharing which allowed general-purpose user programming, including machine language.
: one user at a time with no interactivity. A few pioneering systems such as the Atlas Supervisor
at the University of Manchester
, Compatible Time-Sharing System at MIT, and the Dartmouth Time Sharing System
at Dartmouth College
required large expensive machines.
Implementation started in 1964 with the arrival of the SDS 930
which was modified slightly, and an operating system was written from scratch.
Students who worked on the Berkeley Timesharing System included sophomore L. Peter Deutsch
, graduate student Butler Lampson
and Chuck Thacker.
The heart of the system was the Monitor roughly what is now usually called a kernel
, and the
Executive was roughly what is now usually called a command-line interface
.
When the system was working, Max Palevsky
, founder of Scientific Data Systems
, was at first not interested in selling it as a product. He though timesharing had no commercial demand. However, as other customers expressed interest, it was put on the SDS pricelist as an expensive variant of the 930.
By November 1967 it was being sold commercially as the SDS 940
.
By August 1968 a version 2.0 was announced that was just called the "SDS 940 Time-Sharing System".
Other timesharing systems were generally one-of-a-kind systems, or limited to a single application (such as teaching Dartmouth BASIC
). The 940 was the first to allow for general-purpose programming, and sold about 60 units: not large by today's standards, but it was a significant part of SDS' revenues.
One customer was Bolt, Beranek and Newman
.
The TENEX
operating system for the PDP-10
mainframe computer, used many features of this system, but extended the memory management
to include demand paging
.
Some concepts of the operating system also influenced the design of Unix
, whose designer Ken Thompson
worked on the SDS 940 while at Berkeley.
The QED
text editor
was first implemented by Butler Lampson and L. Peter Deutsch for the Berkeley Timesharing System in 1967.
Another major customer was Tymshare
, who used the system to become the USA's best known commercial timesharing service in the late 1960s. By 1972 Tymshare alone had 23 systems in operation.
Time-sharing
Time-sharing is the sharing of a computing resource among many users by means of multiprogramming and multi-tasking. Its introduction in the 1960s, and emergence as the prominent model of computing in the 1970s, represents a major technological shift in the history of computing.By allowing a large...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
implemented between 1964 and 1967 at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
. It was designed as part of Project Genie
Project Genie
Project Genie was a computer research project started in 1964 at the University of California, Berkeley.It produced an early time-sharing system including the Berkeley Timesharing System, which was then commercialized as the SDS 940.-History:...
and marketed by Scientific Data Systems
Scientific Data Systems
Scientific Data Systems, or SDS, was an American computer company founded in September 1961 by Max Palevsky, a veteran of Packard Bell and Bendix, along with eleven other computer scientists. SDS was an early adopter of integrated circuits in computer design and the first to employ silicon...
for the SDS 940
SDS 940
The SDS 940 was Scientific Data Systems' first machine designed to support time sharing directly, and was based on the SDS 930's 24-bit CPU built primarily of integrated circuits. It was announced in February 1966 and shipped in April, becoming a major part of Tymshare's expansion during the 1960s...
computer system.
It was the first commercial time-sharing which allowed general-purpose user programming, including machine language.
History
In the mid 1960s most computers used batch processingBatch processing
Batch processing is execution of a series of programs on a computer without manual intervention.Batch jobs are set up so they can be run to completion without manual intervention, so all input data is preselected through scripts or command-line parameters...
: one user at a time with no interactivity. A few pioneering systems such as the Atlas Supervisor
Atlas Supervisor
The Atlas Supervisor was the program which managed the allocation of processing resources of Manchester University's Atlas Computer so that the machine was able to act on many tasks and user programs concurrently....
at the University of Manchester
University of Manchester
The University of Manchester is a public research university located in Manchester, United Kingdom. It is a "red brick" university and a member of the Russell Group of research-intensive British universities and the N8 Group...
, Compatible Time-Sharing System at MIT, and the Dartmouth Time Sharing System
Dartmouth Time Sharing System
The Dartmouth Time-Sharing System, or DTSS for short, was the first large-scale time-sharing system to be implemented successfully. DTSS was inspired by a PDP-1-based time-sharing system at Bolt, Beranek and Newman. In 1962, John Kemeny and Thomas Kurtz at Dartmouth College submitted a grant for...
at Dartmouth College
Dartmouth College
Dartmouth College is a private, Ivy League university in Hanover, New Hampshire, United States. The institution comprises a liberal arts college, Dartmouth Medical School, Thayer School of Engineering, and the Tuck School of Business, as well as 19 graduate programs in the arts and sciences...
required large expensive machines.
Implementation started in 1964 with the arrival of the SDS 930
SDS 930
The SDS 930 was a commercial computer using bipolar junction transistors sold by Scientific Data Systems.It was announced in December 1963, with first installations in June 1964.-Description:An SDS 930 system consisted of at least three standard The SDS 930 was a commercial computer using bipolar...
which was modified slightly, and an operating system was written from scratch.
Students who worked on the Berkeley Timesharing System included sophomore L. Peter Deutsch
L. Peter Deutsch
L Peter Deutsch or Peter Deutsch is the founder of Aladdin Enterprises and creator of Ghostscript, a free software PostScript and PDF interpreter....
, graduate student Butler Lampson
Butler Lampson
Butler W. Lampson is a renowned computer scientist.After graduating from the Lawrenceville School , Lampson received his Bachelor's degree in Physics from Harvard University in 1964, and his Ph.D...
and Chuck Thacker.
The heart of the system was the Monitor roughly what is now usually called a kernel
Kernel (computing)
In computing, the kernel is the main component of most computer operating systems; it is a bridge between applications and the actual data processing done at the hardware level. The kernel's responsibilities include managing the system's resources...
, and the
Executive was roughly what is now usually called a command-line interface
Command-line interface
A command-line interface is a mechanism for interacting with a computer operating system or software by typing commands to perform specific tasks...
.
When the system was working, Max Palevsky
Max Palevsky
Max Palevsky was an American art collector, venture capitalist, philanthropist, and computer technology pioneer.-Early life:...
, founder of Scientific Data Systems
Scientific Data Systems
Scientific Data Systems, or SDS, was an American computer company founded in September 1961 by Max Palevsky, a veteran of Packard Bell and Bendix, along with eleven other computer scientists. SDS was an early adopter of integrated circuits in computer design and the first to employ silicon...
, was at first not interested in selling it as a product. He though timesharing had no commercial demand. However, as other customers expressed interest, it was put on the SDS pricelist as an expensive variant of the 930.
By November 1967 it was being sold commercially as the SDS 940
SDS 940
The SDS 940 was Scientific Data Systems' first machine designed to support time sharing directly, and was based on the SDS 930's 24-bit CPU built primarily of integrated circuits. It was announced in February 1966 and shipped in April, becoming a major part of Tymshare's expansion during the 1960s...
.
By August 1968 a version 2.0 was announced that was just called the "SDS 940 Time-Sharing System".
Other timesharing systems were generally one-of-a-kind systems, or limited to a single application (such as teaching Dartmouth BASIC
Dartmouth BASIC
Dartmouth BASIC is the original version of the BASIC programming language. It is so named because it was designed and implemented at Dartmouth College...
). The 940 was the first to allow for general-purpose programming, and sold about 60 units: not large by today's standards, but it was a significant part of SDS' revenues.
One customer was Bolt, Beranek and Newman
BBN Technologies
BBN Technologies is a high-technology company which provides research and development services. BBN is based next to Fresh Pond in Cambridge, Massachusetts, USA...
.
The TENEX
TOPS-20
The TOPS-20 operating system by Digital Equipment Corporation was the second proprietary OS for the PDP-10 mainframe computer. TOPS-20 began in 1969 as the TENEX operating system of Bolt, Beranek and Newman...
operating system for the PDP-10
PDP-10
The PDP-10 was a mainframe computer family manufactured by Digital Equipment Corporation from the late 1960s on; the name stands for "Programmed Data Processor model 10". The first model was delivered in 1966...
mainframe computer, used many features of this system, but extended the memory management
Memory management
Memory management is the act of managing computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and freeing it for reuse when no longer needed. This is critical to the computer system.Several...
to include demand paging
Demand paging
In computer operating systems, demand paging is an application of virtual memory. In a system that uses demand paging, the operating system copies a disk page into physical memory only if an attempt is made to access it...
.
Some concepts of the operating system also influenced the design of Unix
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
, whose designer Ken Thompson
Ken Thompson
Kenneth Lane Thompson , commonly referred to as ken in hacker circles, is an American pioneer of computer science...
worked on the SDS 940 while at Berkeley.
The QED
QED (text editor)
QED is a line-oriented computer text editor that was developed by Butler Lampson and L. Peter Deutsch for the Berkeley Timesharing System running on the SDS 940. It was implemented by L...
text editor
Text editor
A text editor is a type of program used for editing plain text files.Text editors are often provided with operating systems or software development packages, and can be used to change configuration files and programming language source code....
was first implemented by Butler Lampson and L. Peter Deutsch for the Berkeley Timesharing System in 1967.
Another major customer was Tymshare
Tymshare
Tymshare, Inc. was headquartered in Cupertino, California from 1964 to 1984.It was a well-known timesharing service and third-party hardware maintenance company throughout its history and competed with companies such as Four Phase, Compuserve, and Digital Equipment Corporation...
, who used the system to become the USA's best known commercial timesharing service in the late 1960s. By 1972 Tymshare alone had 23 systems in operation.