Origins of TOPS-10
Bob Supnik
reviving Project Genie, the Berkeley timesharing system from the
mid-60s. Looking at the dates, it seems to me that when Genie was
being built, as a research project, TOPS-10 was already shipping, as a
commercial product. What were the research and design origins of the
PDP-6/10 timesharing monitor? Did it descend, in any way, from the
various east coast timesharing research projects of the early 60s:
CTSS and PDP-1 T/S at MIT, PDP-1 T/S at BBN, etc? Or from other
sources?
Thanks,
/Bob
Ken Stailey
Have you seen this page? It suggests that Project Genie influenced
Tenex not TOPS-10.
http://www.cs.berkeley.edu/~pattrsn/Arch/prototypes2.html
<< SDS 940 (1964) Scientific Data Systems (SDS) 940 was designed and
implemented at Berkeley as part of Project Genie. It was subsequently
marketed by SDS as the first commercial time-sharing which allowed
user programming in machine language. About 60 machines were sold, and
they were the initial hardware base for many time-sharing service
companies, including Tymshare. This system was copied directly in the
design of the Tenex system for the PDP-10, except for the memory
management. Tenex later evolved into TOPS-20, the standard operating
system for the DecSystem 20. Some of the 940 system's ideas are also
embodied in Unix, whose designer Ken Thompson worked on the 940 while
at Berkeley. Students who worked on this include Larry Barnes, L.
Peter Deutsch, Wayne Lichtenberger, Butler Lampson, Mel Pirtle, and
Chuck Thacker, and were led by Professor Robert Evans. They modified
an SDS 930 which SDS to add the user/OS protection modes and mapped
the 16 K-word address space into 8 2K-word pages. They also wrote a
timeshared operating system for it. (SDS later sold it as the 940. SDS
was later purchased by Xerox, and became XDS.) The Genie project
eventually led to the Berkeley Computer Corporation (BCC). When BCC
faltered, the employees were recruited by Bob Taylor--who had been the
ARPA program manager of Project Genie--to form the core of Xerox PARC.
>>
Ken Stailey
> Bob Supnik <bsu...@nauticusnet.com> wrote in message news:<ifikeuc3ghudb72id...@4ax.com>...
> > I've been working on an SDS 940 simulator, primarily in the hopes of
> > reviving Project Genie, the Berkeley timesharing system from the
> > mid-60s. Looking at the dates, it seems to me that when Genie was
> > being built, as a research project, TOPS-10 was already shipping, as a
> > commercial product. What were the research and design origins of the
> > PDP-6/10 timesharing monitor? Did it descend, in any way, from the
> > various east coast timesharing research projects of the early 60s:
> > CTSS and PDP-1 T/S at MIT, PDP-1 T/S at BBN, etc? Or from other
> > sources?
> >
> > Thanks,
> >
> > /Bob
>
> Have you seen this page? It suggests that Project Genie influenced
> Tenex not TOPS-10.
>
> http://www.cs.berkeley.edu/~pattrsn/Arch/prototypes2.html
This page mentions that Project Genie influenced UNIX also.
http://cm.bell-labs.com/cm/cs/who/dmr/hist.html
<< Process control in its modern form was designed and implemented
within a couple of days. It is astonishing how easily it fitted into
the existing system; at the same time it is easy to see how some of
the slightly unusual features of the design are present precisely
because they represented small, easily-coded changes to what existed.
A good example is the separation of the fork and exec functions. The
most common model for the creation of new processes involves
specifying a program for the process to execute; in Unix, a forked
process continues to run the same program as its parent until it
performs an explicit exec. The separation of the functions is
certainly not unique to Unix, and in fact it was present in the
Berkeley time-sharing system [2], which was well-known to Thompson.
Still, it seems reasonable to suppose that it exists in Unix mainly
because of the ease with which fork could be implemented without
changing much else. The system already handled multiple (i.e. two)
processes; there was a process table, and the processes were swapped
between main memory and the disk. [...]
2. L. P. Deutch and B. W. Lampson, `SDS 930 Time-sharing System
Preliminary Reference Manual,' Doc. 30.10.10, Project Genie, Univ.
Cal. at Berkeley (April 1965). >>