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> 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? > Wiki

by 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.
- SeenNotHeard 3y ago
  > I expect that by 1975, say, the number of high-end hardware installations was a lot more than 80. Are you sure? Wikipedia notes that for the Cray-1, released in 1975, eventually "eighty Cray-1s were sold, making it one of the most successful supercomputers in history." https://en.wikipedia.org/wiki/Cray-1 https://en.wikipedia.org/wiki/Cray-1 Yes, yes, there's a difference between high-end mainframes and supercomputers, but there's also a difference between mainframes and the PDP-11, which is better categorized as a minicomputer. Personally, I find the dismissal of Multics to be less about reality and more about the perpetuation of pre-existing lore. The Xerox Star and Smalltalk also did not fare well in terms of commercial sales, but they tend to be lionized in computer history rather than treated as a joke.
- msla 3y ago
  > I expect that by 1975, say, the number of high-end hardware installations was a lot more than 80. Yes, part of the problem was that, for all of its goals of portability, Multics only ever ran on two kinds of computer, and depended on their hardware features quite intimately. Compared to Unix, it was not effectively portable. > 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. [snip] > 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. Yes: The computing utility concept came to pass on a smaller scale than the Multics people anticipated, and so could get by with smaller, cheaper, and less reliable hardware and software, which eventually grew up to be more Multics-level in capacity and reliability without becoming as expensive. My point with my original post was to push back on the notion that Multics was a complete failure, that it stagnated and died after Bell Labs left the project. It didn't, it produced an OS that found a tiny commercial niche, and it executed on its vision to the extent the world as a whole allowed it to. The fact the world moved in a different direction doesn't take away from the technical accomplishment of the Multics development team.
  - pjmlp 3y ago
    People keep forgetting that UNIX only became portable after the UNIX V5 rewrite, and thanks to having the source code freely available to anyone that asked for it, for a symbolic price. Until UNIX V5 and the Lions commentary book, it was PDP-7/PDP-11 only.

by msla 3y ago

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.

SeenNotHeard 3y ago
> I expect that by 1975, say, the number of high-end hardware installations was a lot more than 80. Are you sure? Wikipedia notes that for the Cray-1, released in 1975, eventually "eighty Cray-1s were sold, making it one of the most successful supercomputers in history." https://en.wikipedia.org/wiki/Cray-1 https://en.wikipedia.org/wiki/Cray-1 Yes, yes, there's a difference between high-end mainframes and supercomputers, but there's also a difference between mainframes and the PDP-11, which is better categorized as a minicomputer. Personally, I find the dismissal of Multics to be less about reality and more about the perpetuation of pre-existing lore. The Xerox Star and Smalltalk also did not fare well in terms of commercial sales, but they tend to be lionized in computer history rather than treated as a joke.
msla 3y ago
> I expect that by 1975, say, the number of high-end hardware installations was a lot more than 80. Yes, part of the problem was that, for all of its goals of portability, Multics only ever ran on two kinds of computer, and depended on their hardware features quite intimately. Compared to Unix, it was not effectively portable. > 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. [snip] > 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. Yes: The computing utility concept came to pass on a smaller scale than the Multics people anticipated, and so could get by with smaller, cheaper, and less reliable hardware and software, which eventually grew up to be more Multics-level in capacity and reliability without becoming as expensive. My point with my original post was to push back on the notion that Multics was a complete failure, that it stagnated and died after Bell Labs left the project. It didn't, it produced an OS that found a tiny commercial niche, and it executed on its vision to the extent the world as a whole allowed it to. The fact the world moved in a different direction doesn't take away from the technical accomplishment of the Multics development team.
- pjmlp 3y ago
  People keep forgetting that UNIX only became portable after the UNIX V5 rewrite, and thanks to having the source code freely available to anyone that asked for it, for a symbolic price. Until UNIX V5 and the Lions commentary book, it was PDP-7/PDP-11 only.