9 ms·

The Evolution of the Unix Time-Sharing System (1984) [pdf]

121 points by agomez314 3y ago

msla 3y ago
OK, let's take this in some more context: > To the Labs computing community as a whole, the problem was the increasing obviousness of the failure of Multics to deliver promptly any sort of usable system, let alone the panacea envisioned earlier. What was Multics? One core animating idea of Multics was the "Computer Utility" concept, or centralized mainframe-based computing as a utility as reliable and available as water and power: https://multicians.org/fjcc1.html https://multicians.org/fjcc1.html > One of the overall design goals is to create a computing system which is capable of meeting almost all of the present and near-future requirements of a large computer utility. Such systems must run continuously and reliably 7 days a week, 24 hours a day in a way similar to telephone or power systems, and must be capable of meeting wide service demands: from multiple man-machine interaction to the sequential processing of absentee-user jobs; from the use of the system with dedicated languages and subsystems to the programming of the system itself; and from centralized bulk card, tape, and printer facilities to remotely located terminals. Such information processing and communication systems are believed to be essential for the future growth of computer use in business, in industry, in government and in scientific laboratories as well as stimulating applications which would be otherwise undone. -- "Introduction and Overview of the Multics System", F. J. Corbató (MIT) and V. A. Vyssotsky (Bell Labs) This was an ambitious project and it took some time to achieve. Work on Multics started in 1965 and Multics was first used for paying customers in October of 1969, six months after Bell Labs dropped out and work on Unix began. https://multicians.org/chrono.html https://multicians.org/chrono.html So did Multics deliver "promptly"? Probably not, but four years for an ambitious project isn't so bad, and it took Unix six years (until 1975) to get to Sixth Edition, the first version of Research Unix used much outside of Bell Labs. https://en.wikipedia.org/wiki/Version_6_Unix https://en.wikipedia.org/wiki/Version_6_Unix My point is that Multics is given short shrift by this history, which is understandable because it's about a completely different OS, but it's painted as a failure that was stalled in development for an inordinate amount of time. It wasn't a failure, as it was used commercially until 2000, and whether it was inordinately slow in coming is impossible to fairly judge because it was, in most respects, the first of its kind, in that it was the first "complete" OS with what we'd now consider the full complement of functionality.
- cafard 3y ago
  Multics influenced a number of minicomputer OSes of the 1970s. I never used PRIMEOS, but have heard it described as a smaller version of Multics. I did use Data General's AOS/VS, and that had been influenced by Multics--so I suppose that its predecessor AOS also had been.
  - reaperducer 3y ago
    I never used PRIMEOS, but have heard it described as a smaller version of Multics. I've never heard PR1MEOS referred to that way, but it makes a lot of sense. It was a lot easier to wrap one's brain around than the competition.
- AnimalMuppet 3y ago
  Wikipedia says that Multics had "about 80 installations". That's probably a big part of why Multics is given short shrift - it was successfully built, but (approximately) nobody cared. Wikipedia also notes that Unix ran on less expensive hardware than Multics. That mattered - there were many more systems that Unix could be put on.
  - msla 3y ago
    > Wikipedia says that Multics had "about 80 installations". It was a mainframe operating system that only ran on high-end hardware. What do you expect? > Wikipedia also notes that Unix ran on less expensive hardware than Multics. Yes. It was also less capable. Both of those things were design goals of Unix and not of Multics.
    - AnimalMuppet 3y ago
      > It was a mainframe operating system that only ran on high-end hardware. What do you expect? I expect that by 1975, say, the number of high-end hardware installations was a lot more than 80. Multics, even when completed, didn't make much of a dent in the world. The ideas were influential, used in a number of later OSes, but Multics itself didn't go very far. > Yes. It was also less capable. Both of those things were design goals of Unix and not of Multics. Yes. Multics had the wrong design goals. Arguably, it hit them, but that didn't matter, because they were the wrong goals (though not obviously wrong at the time). That's why Multics is given short shrift - it successfully implemented what turned out in retrospect to be the wrong thing. Why were they the wrong goals? There were something like 600,000 PDP-11s sold. Sure, Unix didn't go on all of those, and Multics could have run on more than the 80 machines that it did. Still, that's an insanely large number of installations that they... not exactly ignored, because even the first PDP-11 hadn't shipped when the Multics project began, but at least a huge number of machines that they were unable to serve. And of course, as always happens in this business, the lower-end machines became more and more powerful. The result of that (plus easier portability) was that Unix ate the world, and Multics became a footnote.
theodpHN 3y ago
What's the state of 'traditional' turnkey time sharing for coding + development in 2023? Are always-on, signon-and-go servers or clusters of servers with shared storage and a wealth of pre-installed software used by a community of scores or hundreds or thousands of developers still a common thing? Or has that pretty much gone by the wayside and most development is carried out in more isolated, individualized, single-user oriented environments - be it laptop/desktop or Cloud-based (containers, VMs, EC2, etc.) that are customized/tailored to single individual's needs?
- GMoromisato 3y ago
  I don't know about "traditional" systems, but I'm trying to create a modern time-share system for building web apps. There's a work in progress at: https://gridwhale.com https://gridwhale.com. (Warning: Still primitive and lots of bugs). My manifesto is here: https://medium.com/@gridwhale/rise-of-the-hyperplatforms-d4a148e608de https://medium.com/@gridwhale/rise-of-the-hyperplatforms-d4a...
- packetlost 3y ago
  I'm not sure if this is what you're getting at, but the tilde[0] and SDF[1] communities are going pretty strong still. Both of them amount to getting a shell account on a shared box with a bunch of pre-installed/hosted utilities. Much more hobbyist-centric than professional though. [0]: https://tildeverse.org https://tildeverse.org [1]: https://sdf.org https://sdf.org
- kedean 3y ago
  Supercomputing environments I've encountered are still timesharing-based, because by definition they are too expensive to be single-user. My old university still operates a cluster-based system that you can submit jobs to, with "head nodes" that have ssh access for light work/setup (they aren't suited for heavy jobs). It's operated by the CS dept but available for others to use, the sciences in particular.
  - sneed_chucker 3y ago
    From what I've seen at FAANG companies, GPU clusters for ML researchers are similar. Basically a bunch of beefy nodes with 96 CPUs and 8 Nvidia A100 cards each configured in a SLURM cluster. Users get SSH access and can run tmux, jupyter, or whatever else is needed for their workflow.
bluetomcat 3y ago
> the charter sought was not merely to write some (unspecified) operating system, but instead to create a system specifically designed for editing and formatting text, what might today be called a ‘word-processing system.’ That's an interesting perspective. Was the shell intended to be a glorified word processor, with tools like sort, uniq, wc? In a documentary from the early 1980s, Kernighan also demonstrates this as a "killer" feature of Unix: https://www.youtube.com/watch?v=tc4ROCJYbm0 https://www.youtube.com/watch?v=tc4ROCJYbm0
- Beermotor 3y ago
  IIRC it was initially employed for their payroll system to help print checks.
  - p_l 3y ago
    First commercial use in Bell Labs is usually credited as the secretarial pool for writing patent applications.
    - somat 3y ago
      I always give an ironic chuckle when fighting the print system on a unix machine(lpd, lp, cups...) the internal rant that goes with it is something like. "Printing was THE original purpose, the reason for existence, of unix, you would think it would be a solved problem instead of the terrible mismatch of sins that it is."
      - screechingbagel 3y ago
        printing on unix in my experience is quite painless compared to windows for example, in my experience it just works :p
- MarkusWandel 3y ago
  Here's Ken Thompson talking about it (the word processing angle) quite entertainingly: https://youtu.be/EY6q5dv_B-o?t=1494 https://youtu.be/EY6q5dv_B-o?t=1494
genr8 3y ago
What a coincidence, - I was reading about this last night on a great website: https://www.multicians.org/project-mac.html https://www.multicians.org/project-mac.html
- pcarion 3y ago
  link is not working (Forbidden)

121 points by agomez314 3y ago

msla 3y ago

OK, let's take this in some more context: > To the Labs computing community as a whole, the problem was the increasing obviousness of the failure of Multics to deliver promptly any sort of usable system, let alone the panacea envisioned earlier. What was Multics? One core animating idea of Multics was the "Computer Utility" concept, or centralized mainframe-based computing as a utility as reliable and available as water and power: https://multicians.org/fjcc1.html https://multicians.org/fjcc1.html > One of the overall design goals is to create a computing system which is capable of meeting almost all of the present and near-future requirements of a large computer utility. Such systems must run continuously and reliably 7 days a week, 24 hours a day in a way similar to telephone or power systems, and must be capable of meeting wide service demands: from multiple man-machine interaction to the sequential processing of absentee-user jobs; from the use of the system with dedicated languages and subsystems to the programming of the system itself; and from centralized bulk card, tape, and printer facilities to remotely located terminals. Such information processing and communication systems are believed to be essential for the future growth of computer use in business, in industry, in government and in scientific laboratories as well as stimulating applications which would be otherwise undone. -- "Introduction and Overview of the Multics System", F. J. Corbató (MIT) and V. A. Vyssotsky (Bell Labs) This was an ambitious project and it took some time to achieve. Work on Multics started in 1965 and Multics was first used for paying customers in October of 1969, six months after Bell Labs dropped out and work on Unix began. https://multicians.org/chrono.html https://multicians.org/chrono.html So did Multics deliver "promptly"? Probably not, but four years for an ambitious project isn't so bad, and it took Unix six years (until 1975) to get to Sixth Edition, the first version of Research Unix used much outside of Bell Labs. https://en.wikipedia.org/wiki/Version_6_Unix https://en.wikipedia.org/wiki/Version_6_Unix My point is that Multics is given short shrift by this history, which is understandable because it's about a completely different OS, but it's painted as a failure that was stalled in development for an inordinate amount of time. It wasn't a failure, as it was used commercially until 2000, and whether it was inordinately slow in coming is impossible to fairly judge because it was, in most respects, the first of its kind, in that it was the first "complete" OS with what we'd now consider the full complement of functionality.

cafard 3y ago
Multics influenced a number of minicomputer OSes of the 1970s. I never used PRIMEOS, but have heard it described as a smaller version of Multics. I did use Data General's AOS/VS, and that had been influenced by Multics--so I suppose that its predecessor AOS also had been.
- reaperducer 3y ago
  I never used PRIMEOS, but have heard it described as a smaller version of Multics. I've never heard PR1MEOS referred to that way, but it makes a lot of sense. It was a lot easier to wrap one's brain around than the competition.
AnimalMuppet 3y ago
Wikipedia says that Multics had "about 80 installations". That's probably a big part of why Multics is given short shrift - it was successfully built, but (approximately) nobody cared. Wikipedia also notes that Unix ran on less expensive hardware than Multics. That mattered - there were many more systems that Unix could be put on.
- msla 3y ago
  > Wikipedia says that Multics had "about 80 installations". It was a mainframe operating system that only ran on high-end hardware. What do you expect? > Wikipedia also notes that Unix ran on less expensive hardware than Multics. Yes. It was also less capable. Both of those things were design goals of Unix and not of Multics.
  - AnimalMuppet 3y ago
    > It was a mainframe operating system that only ran on high-end hardware. What do you expect? I expect that by 1975, say, the number of high-end hardware installations was a lot more than 80. Multics, even when completed, didn't make much of a dent in the world. The ideas were influential, used in a number of later OSes, but Multics itself didn't go very far. > Yes. It was also less capable. Both of those things were design goals of Unix and not of Multics. Yes. Multics had the wrong design goals. Arguably, it hit them, but that didn't matter, because they were the wrong goals (though not obviously wrong at the time). That's why Multics is given short shrift - it successfully implemented what turned out in retrospect to be the wrong thing. Why were they the wrong goals? There were something like 600,000 PDP-11s sold. Sure, Unix didn't go on all of those, and Multics could have run on more than the 80 machines that it did. Still, that's an insanely large number of installations that they... not exactly ignored, because even the first PDP-11 hadn't shipped when the Multics project began, but at least a huge number of machines that they were unable to serve. And of course, as always happens in this business, the lower-end machines became more and more powerful. The result of that (plus easier portability) was that Unix ate the world, and Multics became a footnote.

theodpHN 3y ago

What's the state of 'traditional' turnkey time sharing for coding + development in 2023? Are always-on, signon-and-go servers or clusters of servers with shared storage and a wealth of pre-installed software used by a community of scores or hundreds or thousands of developers still a common thing? Or has that pretty much gone by the wayside and most development is carried out in more isolated, individualized, single-user oriented environments - be it laptop/desktop or Cloud-based (containers, VMs, EC2, etc.) that are customized/tailored to single individual's needs?

GMoromisato 3y ago
I don't know about "traditional" systems, but I'm trying to create a modern time-share system for building web apps. There's a work in progress at: https://gridwhale.com https://gridwhale.com. (Warning: Still primitive and lots of bugs). My manifesto is here: https://medium.com/@gridwhale/rise-of-the-hyperplatforms-d4a148e608de https://medium.com/@gridwhale/rise-of-the-hyperplatforms-d4a...
packetlost 3y ago
I'm not sure if this is what you're getting at, but the tilde[0] and SDF[1] communities are going pretty strong still. Both of them amount to getting a shell account on a shared box with a bunch of pre-installed/hosted utilities. Much more hobbyist-centric than professional though. [0]: https://tildeverse.org https://tildeverse.org [1]: https://sdf.org https://sdf.org
kedean 3y ago
Supercomputing environments I've encountered are still timesharing-based, because by definition they are too expensive to be single-user. My old university still operates a cluster-based system that you can submit jobs to, with "head nodes" that have ssh access for light work/setup (they aren't suited for heavy jobs). It's operated by the CS dept but available for others to use, the sciences in particular.
- sneed_chucker 3y ago
  From what I've seen at FAANG companies, GPU clusters for ML researchers are similar. Basically a bunch of beefy nodes with 96 CPUs and 8 Nvidia A100 cards each configured in a SLURM cluster. Users get SSH access and can run tmux, jupyter, or whatever else is needed for their workflow.

bluetomcat 3y ago

> the charter sought was not merely to write some (unspecified) operating system, but instead to create a system specifically designed for editing and formatting text, what might today be called a ‘word-processing system.’ That's an interesting perspective. Was the shell intended to be a glorified word processor, with tools like sort, uniq, wc? In a documentary from the early 1980s, Kernighan also demonstrates this as a "killer" feature of Unix: https://www.youtube.com/watch?v=tc4ROCJYbm0 https://www.youtube.com/watch?v=tc4ROCJYbm0

Beermotor 3y ago
IIRC it was initially employed for their payroll system to help print checks.
- p_l 3y ago
  First commercial use in Bell Labs is usually credited as the secretarial pool for writing patent applications.
  - somat 3y ago
    I always give an ironic chuckle when fighting the print system on a unix machine(lpd, lp, cups...) the internal rant that goes with it is something like. "Printing was THE original purpose, the reason for existence, of unix, you would think it would be a solved problem instead of the terrible mismatch of sins that it is."
    - screechingbagel 3y ago
      printing on unix in my experience is quite painless compared to windows for example, in my experience it just works :p
MarkusWandel 3y ago
Here's Ken Thompson talking about it (the word processing angle) quite entertainingly: https://youtu.be/EY6q5dv_B-o?t=1494 https://youtu.be/EY6q5dv_B-o?t=1494

genr8 3y ago

What a coincidence, - I was reading about this last night on a great website: https://www.multicians.org/project-mac.html https://www.multicians.org/project-mac.html

pcarion 3y ago
link is not working (Forbidden)