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Prof. Andy Tanenbaum Retires From Vrije University

When Linus Torvalds first announced his new operating system project ("just a hobby, won't be big and professional like gnu"), he aimed the announcement at users of Minix for a good reason: Minix (you can download the latest from the Minix home page) was the kind of OS that tinkerers could afford to look at, and it was intended as an educational tool. Minix's creator, Professor Andrew Stuart "Andy" Tanenbaum, described his academic-oriented microkernel OS as a hobby, too, in the now-famous online discussion with Linus and others. New submitter Thijssss (655388) writes with word that Tanenbaum, whose educational endeavors led indirectly to the birth of Linux, is finally retiring. "He has been at the Vrije Universiteit for 43 years, but everything must eventually end."

96 of 136 comments (clear)

  1. His epitaph in future years: by halivar · · Score: 5, Funny

    "Microkernels are still better, you little punk!" With an engraving of a shaking fist.

    1. Re:His epitaph in future years: by MightyMartian · · Score: 4, Interesting

      I really miss the good old days when technical debates were over the merits and faults of such simple things as different kinds of kernels, and not about whether or not every single thing you do online is being stacked into half a dozen nation's permanent data storage facilities.

      The Linus vs. Tanenbaum dustup is from a simpler, more positive age.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    2. Re:His epitaph in future years: by StripedCow · · Score: 1

      Yes, but look where that age took us!

      --
      If Pandora's box is destined to be opened, *I* want to be the one to open it.
    3. Re:His epitaph in future years: by rubycodez · · Score: 3, Insightful

      eh, all that good old stuff is in a national permanent storage system called Usenet archives

    4. Re:His epitaph in future years: by TeknoHog · · Score: 5, Funny

      The Linus vs. Tanenbaum dustup is from a simpler, more positive age.

      It's your father's microkernel. A more elegant weapon for a more civilized age.

      --
      Escher was the first MC and Giger invented the HR department.
    5. Re:His epitaph in future years: by itzly · · Score: 2

      We can still hope he'll come to his senses before that.

    6. Re:His epitaph in future years: by Z00L00K · · Score: 2

      Both architectures have their merits. I wouldn't say that one is better than the other.

      At least Minix has come a long way since the late 80's where any crash after an uptime of more than 2 hours could be attributed to the OS instead of the application.

      --
      If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
    7. Re:His epitaph in future years: by invictusvoyd · · Score: 1

      When Torvalds said that "microkernels are like masturbation. It feels good but you dont get anything done" . I wonder if he was right . The folks at HURD are still kinda .. shagging with their kernel.

    8. Re:His epitaph in future years: by jbolden · · Score: 1

      I'd say that HURD is just a failed product and not read too much into it. QNX has been out for a long time with a terrific microkernel that offers real advantages. Its about to become too dated as their isn't going to be the funding to make the move to 64 bit but... Moreover arguably the virtualization OSes are essentially microkernels where a virtualization system acts as a mini kernel, multiple non-monolythic kernels operate on top of them and then branch out. Virtualization hasn't exactly been a failure. There are substantial advantages to both approaches and frankly Linus ended up introducing a modules system to capture many of the advantages of microkernels himself.

  2. "Vrije University"? by RGuns · · Score: 4, Informative

    "Vrije" is a Dutch adjective, meaning "free". So either you write "vrije Universiteit", or you write "Free University". "Vrije University" is just silly.

    1. Re:"Vrije University"? by kruach+aum · · Score: 4, Informative

      Pretty sure it's Vrije Universiteit, because the whole functions as a name. In fact, to distinguish it from the one in Brussels, it should probably be referred to as Vrije Universiteit Amsterdam.

    2. Re:"Vrije University"? by Trepidity · · Score: 4, Funny

      But then it gets ambiguous, because someone might think you mean Free University as in no tuition, rather than Free-as-in-Freedom University. And Liberty University is already taken.

    3. Re:"Vrije University"? by gnupun · · Score: 2

      Vrije is pronounced "Fria." "Free University" and "Fria University" kinda sound the same.

    4. Re:"Vrije University"? by Racemaniac · · Score: 1

      Vrije is pronounced "Fria."

      lol, no it isn't XD

    5. Re:"Vrije University"? by CAPSLOCK2000 · · Score: 1

      That's "free" as in "freedom", not as in "free beer".

    6. Re:"Vrije University"? by tepples · · Score: 1

      Is it closer to "fryer"? (Slashdot's Unicode code point whitelist unfortunately doesn't include IPA.)

    7. Re:"Vrije University"? by RyuuzakiTetsuya · · Score: 5, Funny

      Split it down the middle. GNUversity

      --
      Non impediti ratione cogitationus.
    8. Re:"Vrije University"? by Powys · · Score: 1

      What about "Libre University" then?

    9. Re:"Vrije University"? by rogoshen1 · · Score: 3, Funny

      Good, IPA's are way too hoppy.

    10. Re:"Vrije University"? by TheRaven64 · · Score: 2

      This is confusing in Brussels, because there is Université libre de Bruxelles (Free University of Brussels), but there is also Vrije Universiteit Brussel (Free University of Brussels), a different university.

      --
      I am TheRaven on Soylent News
    11. Re:"Vrije University"? by tverbeek · · Score: 1

      And Liberty University is already taken.

      Liberty University is called that instead of "Free University" because it is neither free-as-in-beer nor free-as-in-speech. It teaches the religion of Capitalism and the legal principles of the Bible.

      --
      http://alternatives.rzero.com/
    12. Re:"Vrije University"? by PolygamousRanchKid+ · · Score: 1

      Is it closer to "fryer"?

      Awesome! Fryer University, as in bacon!

      . . . do they fry up weed along with your bacon in Holland . . . ? That would be a formidable combination:

      "Eggs, bacon, weed and Spam . . ."

      --
      Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
    13. Re:"Vrije University"? by tverbeek · · Score: 1

      You'd at least capitalize it as "Vrije Universiteit", because it's a proper noun* and those are capitalized (in either English or Dutch).

      *Not just a free university, but the Free University.

      --
      http://alternatives.rzero.com/
    14. Re:"Vrije University"? by Mister+Liberty · · Score: 1

      Free in the sense: free to teach according to their Reformed Church biblical and religous views.
      That's what the VU was created for by Abraham Kuyper (see wiki).
      Meantime, hat's off for Prof. Tanenbaum.

  3. Aaaaahahaha ... gotta love it: by Qbertino · · Score: 4, Insightful

    "A multithreaded file system is only a performance hack. When there is only one job active, the normal case on a small PC, it buys you nothing and adds complexity to the code. On machines fast enough to support multiple users, you probably have enough buffer cache to insure a hit cache hit rate, in which case multithreading also buys you nothing." - Andy Tanenbaum on the "LINUX is obsolete" Thread from 30 Jan '92

    Nice to see a so called "expert" so far off. Seriously, not the first CS Professor to be completely backwards. I've met a few of those too. :-)

    --
    We suffer more in our imagination than in reality. - Seneca
    1. Re:Aaaaahahaha ... gotta love it: by Anonymous Coward · · Score: 1

      What do you mean? Seems like a sensible comment for the time.

    2. Re:Aaaaahahaha ... gotta love it: by jedidiah · · Score: 2

      No. It was not a "sensible" comment for the time. Anyone with a lick of sense could see where the tech was going and could easily realize that you had to plan for the future.

      PCs of the time were stuck in the kind of situation that Tannenbaum described not because of any inherent technical limitation but because Microsoft was a lame monopolistic sandbagger holding back the entire industry.

      Even in 1992 there wasn't that much of a gap between the capabilities of proprietary Unix hardware and PCs. Some Unix machines even ran on microprocessors used by competing home computers.

      That's why Linus created his own kernel to begin with.

      --
      A Pirate and a Puritan look the same on a balance sheet.
    3. Re:Aaaaahahaha ... gotta love it: by Anonymous Coward · · Score: 1, Interesting

      Even today there is usually one process grabbing most of the CPU time, and even worse, it's additionally fiddling thumbs for long periods as it waits for the slow mechanical HDD. Provided with a nice large buffer, in most scenarios Andy's single-threaded file system access would still serve single-user desktop machines quite well.

    4. Re:Aaaaahahaha ... gotta love it: by Megol · · Score: 4, Interesting

      In 1992, on a small PC this is true. That doesn't mean it was true for a multi-user design. Remember that for a "small PC" the disk interface was ATA without (usable) DMA support and no of the later features to lower CPU overhead - this means that a good buffer cache implementation would provide better performance not only in throughput and latency of disk accesses but also lower wasted CPU cycles proportional to the size of the cache.

      But using ATA also means that the performance of multi-threaded filesystems are unlikely to be much faster than a single threaded one, this because the bottleneck stays the same and also loads the CPU.

      A bigger PC intended as workstations (yes, there were some) would probably use SCSI instead of ATA and then the situation is a bit different. But the original quote is still true IMHO.

    5. Re:Aaaaahahaha ... gotta love it: by LWATCDR · · Score: 2

      Except he was right in 1992.
      He just underestimated the growth in speed and power of a PC. On a 386 with 4 megs of memory and a single slow hard drive he was right.

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    6. Re:Aaaaahahaha ... gotta love it: by itzly · · Score: 1

      No, in 1992 we still used floppies. Also, since in Unix everything is a file, the file system also comes into play when accessing device nodes. Without multithreading, the harddisk access could be stuck in the queue behind a floppy or terminal access. This is simply unacceptable.

    7. Re:Aaaaahahaha ... gotta love it: by Anonymous Coward · · Score: 1

      It was ridiculous. Personal computers have these things called interrupts. They allow the system to do what appears to be many things at once. Waiting for your tape to write shouldn't lock the keyboard, likewise with updating the screen. This is going back into the 1970s, something a professor should have understood. But alas, these people are stuck in their ancient thoughts even back then. Most of my CS hardware lectures were based around paper-tape and punched cards, magnetic media was currently very common, but these old prof's had little experience of them, so they pretty much skipped them. He made is daft comment in the early 90s, when multitasking OSes had long since been on the market for consumers.

    8. Re:Aaaaahahaha ... gotta love it: by Anonymous Coward · · Score: 2

      It wasn't a sensible comment for anyone who could see the writing on the wall. If you weren't in academentia, you could see that it wouldn't be long before personal computers would have more than one process active at a time.

      (Even at the time, it wasn't exactly the future. The Amiga was minor marketshare, but not obscure.)

      I think it's irrelevant, though. I still (in 2014!) think of filesystems as being primarily I/O bound. For the most part, filesystems still just wait for things and don't take a lot of CPU.

      If there's a "future" (by 1991 standards) to be seen, it's not so much "busy computers" or multi-user, but it's doing to be features like checksumming, deduplication, or maybe some nasty cases like maildirs (where something might hunt through a large inefficient data structure and takes a long time, but most things aren't like that) or maybe really fast block devices like SSDs or enormous RAID0s. The maildir example isn't really even futuristic, I'll admit. But mostly, if your filesystem is CPU-bound, then either something relatively unusual is happening, or something is broken! (In a microkernel I'd address the maildir case by having that mountpoint's filesystem be a specialist intended to deal with that particular problem (i.e. don't have an inefficient data structure, even if that means you pay some others costs). Interestingly, I think I'm sort of already doing that with Linux, maildirs being the only remaining situation where I'm still using ReiserFS.)

      Given a situation like that, whatever your multithreaded filesystem is doing, I can envision the same damn thing as a single thread in a single process that's taking a bunch of async file requests and turning them into a series of block requests forwarded to block drivers that are typically going to slowly handle them one a time, perhaps with some elevator re-ordering. And that block driver is going to be "slow" no matter what OS you're running.

      And if you do have something CPU-bound in there, it's not like microkernels can't spin off threads or launch sub-processes to do work. I'm not familiar enough with Minix to say WTF Linus was talking about there, but I bet it's a Minix problem rather than a microkernel problem.

      So what I'm saying is that by the standards of any time (whether 1991 or 2014) single-threaded filesystems are not usually bottlenecks, and in the exceptional cases where they might be (because the filesystem needs to do something CPU-bound), microkernels are not your problem. Tanenbaum was not foolish.

      I use Linux and I love its performance but even in 2014 it would take some work to persuade me that its ability to multithread within filesystems is important. I think we just happen to have some great filesystems that a lot of people have put a lot of work into. A lot more engineering goes into them now than in 1991. Just like the all the things that have changed in userspace! You don't have to be in kernelspace to take problems seriously.

      Also, Tanenbaum was right that the harder you're working your machine, the more likely you have more RAM and might get more cache hits. I'm amazed anyone would imply otherwise. "Add RAM to make things faster" is hardly a sooper-seekrit performance tip. WTF?

    9. Re:Aaaaahahaha ... gotta love it: by SuiteSisterMary · · Score: 1

      He might as well have said '640k should be enough for anyone.'

      --
      Vintage computer games and RPG books available. Email me if you're interested.
    10. Re:Aaaaahahaha ... gotta love it: by mattack2 · · Score: 1

      Who are you calling we, kemosabe?

      I had a 105 meg external drive by 1992 (I think it might have been easily 1-2 years before that). Actually, I had an 80 meg external before that (put into a case).. the 105 was a prebuilt "external" drive.

    11. Re:Aaaaahahaha ... gotta love it: by MightyMartian · · Score: 1

      At the time, the closest the DOS world had to multitasking was TSRs. Beside my first PC was my CoCo 3 with OS/9 level 2 with 512k of RAM with a true preemptive multitasking kernel running on an 8 but 6809 CPU. Microsoft's dominance at the time meant in many ways the most common 16 bit opposing system in the world was only marginally better than a CPM machine from 1980.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    12. Re:Aaaaahahaha ... gotta love it: by mdielmann · · Score: 1

      As is so often the case, context is quite relevant. His statement is ridiculous today, but when it was made, quite reasonable.

      --
      Sure I'm paranoid, but am I paranoid enough?
  4. ATtiny85 by ArcadeMan · · Score: 1

    I don't need no stinkin' OS.

  5. A legend of OS design by sg_oneill · · Score: 5, Insightful

    A lot of people have the wrong impression about the good professor after the infamous exchange, but they miss that this is what academics do, and despite the flameyness of the exchange, Linus and Tanenbaum had a great deal of respect for each other. After all Linus was, for all purposes, Tanenbaums greatest student. I remember borrowing his book from UWA and getting the disks from the UWA computer club, following the instructions to get a functional minix up, then following his book to write a driver for my highly bugshit WANG (yes that was the brand name lol) hard drive controller. I learned more from that about how computers *really* work, than almost any thing I've ever learned. The difficulty of his book was notorious, probably the only books I found harder was Walter Pistons music theory book "Harmony", and Deleuzes philosophy text "Capitalism and Schizophrenia". And like those books, in its field Tanenbaums work shook the foundations of academia.

    Enjoy your retirement old man, you deserved it.

    --
    Excuse the Unicode crap in my posts. That's an apostrophe, and slashdot is busted.
    1. Re:A legend of OS design by MightyMartian · · Score: 4, Interesting

      Minix was really the first of its kind; a Unix-like OS that you could run on cheap (relatively speaking at the time) commodity hardware and that you could get the source code for. A lot of the computing we take for granted now comes from Tanenbaum's work.

      My first Minix install was on a 386-SX with a whopping 4mb of RAM I borrowed from work back in the early 1990s. I quickly abandoned Minix for Linux once it came out, but for several years I had Minix running on an old 386 laptop just for fun.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    2. Re:A legend of OS design by sg_oneill · · Score: 3, Interesting

      Part of the reason I used Minix was I had an old second hand 286. because I couldn't afford one of the new-fangled 386s. Computers where bloody expensive back then! At the time I had started using a local BBS called "Omen" which had just gotten a brand spanking new ISDN connection to this new thing called "ARPAnet" (aka "Australian research something something net") , aka the australian wing of the internet, and it had two amazing features 1) IRC, 2) Usenet (There was also Gopher but eh..... Usenet was better indexed and also had hilarious flame wars). Anyway it struck me that if I had a unix I could get a SLIP connection to the internet and run IRC *and* Usenet simultaneously using the magical wonder of multitasking. Omen was using Linux (very very brand new) but since I didnt have a 386 I couldnt use it. So I grabbed Minix, since I couldnt afford Xenix or SCO Unix (Pre SCO getting brought out by Caldera and then turning cthulhu it was a great company).

      Problem is Minix didnt have a network stack :(

      --
      Excuse the Unicode crap in my posts. That's an apostrophe, and slashdot is busted.
    3. Re:A legend of OS design by Immerman · · Score: 1

      Ah, but is it the man or the deserving that the past tense is referring to? Perhaps he deserved a good retirement 20 years ago,but has since become a world-champion puppy-kicker and is no longer deserving of it?

      And no, I don't actually know enough about the guy to make any such assertion.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    4. Re:A legend of OS design by McGruber · · Score: 3, Interesting

      Minix was really the first of its kind; a Unix-like OS that you could run on cheap (relatively speaking at the time) commodity hardware and that you could get the source code for. A lot of the computing we take for granted now comes from Tanenbaum's work.

      Truly!

      I first learned of Minix by reading about it in Byte magazine. At the time, I was an undergrad at a big US university, a member of the Association of American Universities. The only multitasking computers on the entire campus were a Unix mainframe, a VAX, and a cluster (lab) of Sun workstations that only graduate engineering students could have accounts on. The Unix and VAX machines could be accessed using VT-100 (and later) terminals in computer labs spread out all over the campus. There were also BYOF (Bring Your Own Floppies) computer labs filled with DOS (pre-windows) PCs, and a few labs filled with early Macs, but those labs were mostly used by humanities majors hunting-and-pecking their term papers out.

      Booting a multitasking unix-like OS on a personal computer was a huge deal back then.

    5. Re:A legend of OS design by Anonymous Coward · · Score: 1

      ... this new thing called "ARPAnet" (aka "Australian research something something net") , aka the australian wing of the internet ...

      ARPANET is the Advanced Research Projects Agency Network.

    6. Re:A legend of OS design by sg_oneill · · Score: 1

      Yeah your right. The australian one was AARNet (Australian academic research network)

      --
      Excuse the Unicode crap in my posts. That's an apostrophe, and slashdot is busted.
    7. Re:A legend of OS design by TechNeilogy · · Score: 1

      His books educated more than one generation of programmers and computer scientists. I can remember the decision, while I was a grad student, to part with a sizeable fraction of my net worth to buy my first Tanenbaum textbook. No regrets.

      --
      "The wisdom of the Patriarchs was that they *knew* they were fools." --Master Foo
  6. What I remember by Anonymous Coward · · Score: 2, Interesting

    More than Minix, I remember Tanenbaum for his "Computer Networks" textbook. Especially this:

    "The nice thing about standards is that you have so many to choose from; furthermore, if you do not like any of them, you can just wait for next year's model."

    1. Re:What I remember by swb · · Score: 1

      Maybe an An-225 full of a 6 TB hard disks?

    2. Re:What I remember by Anonymous Coward · · Score: 1

      http://www.dansdata.com/gz105.htm

    3. Re:What I remember by Kohenkatz · · Score: 1

      OK. My curiosity got the better of me, so here it is.

      First, using his number of 82.5 cubic millimeters for the volume of a Micro SD card, and Wikipedia's 1,134 cubic meters for the cargo volume of an A380 (in freight configuration), I get 13745454545 cards. Using his 20% density reduction, I'll bring that down to 10996363636. 128GB MicroSD cards exist, but they aren't mainstream yet, so let's go with 64GB. The total data capacity of the plane is therefore 610.4 EiB (exbibytes), which Wolfram Alpha helpfully says is about 0.7 times the estimated global IP data traffic per year by 2015, and around 59 times the estimated information content of all human knowledge as of mid-1999.

      I looked around to see if I could find anything higher-density than MicroSD, but there isn't really anything. Full-size SD cards are readily available up to 256GB, but they are significantly more than the volume of 4 MicroSD cards. mSATA SSDs are even worse - they are available up to 1 TB, but they are way too big.

    4. Re:What I remember by Kohenkatz · · Score: 1

      ... 6 TB hard disks?

      6 TB hard disks are going to be significantly less efficient. 6TB of 64GB MicroSD cards would be 96 cards which will take up 7.92 cm^3. A 6TB hard drive is huge by comparison, close to 400 cm^3 (though the actual number varies by drive manufacturer).

    5. Re:What I remember by tuxicle · · Score: 1

      Yes, but the TSA will want to inspect each of those flash drives, so the effective bandwidth would be quite low. At least in the US. Maybe that's why we have such atrocious broadband connectivity.

  7. Vrije University? by De+Lemming · · Score: 2

    "Vrije University" in the title sounds realy strange to me, as a native Dutch speaker. Vrije isn't a city, "Vrije Universiteit" means "Free University," which indicates it's not linked to e.g. the Catholic church. Just FYI.

    1. Re:Vrije University? by Anonymous Coward · · Score: 1

      It's doesn't indicate it's not linked to the Catholic Church but that it's not linked to government.

      The Vrije Universiteit was/is the university of a the Gereformeerde kerk (reformed church) witch is a church that split of of the Dutch Reformed Church. They Dutch Reformed church was a semi-controlled by the government and to free/liberal for the tastes of the Gereformeerden.

    2. Re:Vrije University? by Rashdot · · Score: 1

      The word 'Free" in its name is a bit misleading. The university was founded by "a group of orthodox-Protestant Christians" (English Wikipedia page):

      http://en.wikipedia.org/wiki/VU_University_Amsterdam

      --
      This is not the sig you're looking for.
  8. Does this mean the death of Minix3? by Chrisq · · Score: 2

    Does this mean the death of Minix3? That would be a shame I'd like to have seen a good open-source microkernel OS - a sort of "open source OSX".

    1. Re:Does this mean the death of Minix3? by Anonymous Coward · · Score: 4, Informative

      Despite Prof. Tanenbaum's retirement, the MINIX 3 project will continue as a volunteer-based open-source project. A major new release will be out in the Fall and will include support for the ARM processors and the BeagleBone boards. Check the Website periodically for the announcement.

    2. Re:Does this mean the death of Minix3? by plasticsquirrel · · Score: 4, Interesting

      Minix 3 will probably keep going as an open-source project, and maybe he will be even more involved?

      I feel it necessary to point out, though, that OS X is not a microkernel system comparable to Minix. OS X is largely monolithic, so if one part of the core system crashes, the whole system crashes. Minix 3 is far more ambitious because everything that is not in the (truly tiny) microkernel runs as a separate server process. For example, drivers are running in their own process, so if a driver crashes, the rest of the system can continue running.

      To manage the system, Minix has a so-called "reincarnation server" that restarts core system daemons if they go down unexpectedly. It's totally modular and redundant -- far more ambitious and advanced in its design than Linux or OS X. Minix is designed from the beginning to never go down. There is nothing else like that in the Unix world.

      This talk by Tanenbaum describes the Minix 3 design in much greater detail:

      Youtube: MINIX 3: a Modular, Self-Healing POSIX-compatible Operating System

      --
      Systemd: the PulseAudio of init systems
    3. Re:Does this mean the death of Minix3? by drerwk · · Score: 1

      Does this mean the death of Minix3? That would be a shame I'd like to have seen a good open-source microkernel OS - a sort of "open source OSX".

      http://en.wikipedia.org/wiki/D... is Open Source OSX. http://www.opensource.apple.co...

    4. Re:Does this mean the death of Minix3? by TheRaven64 · · Score: 1

      I feel it necessary to point out, though, that OS X is not a microkernel system comparable to Minix

      While this is true, it's worth noting that a lot of the compartmentalisation and sandboxing ideas that most of the userland programs on OS X employ (either directly or via standard APIs) have roots in microkernel research. OS X is in the somewhat odd situation of having userspace processes that are a lot more like multiserver microkernels than its kernel...

      --
      I am TheRaven on Soylent News
    5. Re:Does this mean the death of Minix3? by DamnOregonian · · Score: 1

      OSX does have some portions of it with a microkernel architecture, complete with userspace servers, but the vast majority of it deals with talking back and forth to the massive monolithic BSD tumor grafted onto the side of Mach. I guess you could technically call it a "hybrid", but for most intents and purposes, it's a monolithic kernel with some microkernel primitives that are bloody awkward to use.

      Of all the kernel work I've done, there's nothing more vile than working with Darwin, while Minix, complete with its shortcomings is actually a breeze to work in.

    6. Re:Does this mean the death of Minix3? by DamnOregonian · · Score: 1

      Userspace processes that also function as servers for the microkernel that do most of their heavy lifting with the monolithic BSD skin graft. It's bizarre, ugly, and a nightmare to work with.

    7. Re:Does this mean the death of Minix3? by Carewolf · · Score: 1

      To manage the system, Minix has a so-called "reincarnation server" that restarts core system daemons if they go down unexpectedly. It's totally modular and redundant -- far more ambitious and advanced in its design than Linux or OS X. Minix is designed from the beginning to never go down. There is nothing else like that in the Unix world.

      QNX?

    8. Re:Does this mean the death of Minix3? by unixisc · · Score: 1

      Minix3 is a BSDL OS. So even if AST stops working on it, others can take the code as it is, and build it further, fork it or do whatever

  9. His other project -- electoral-vote.com by MAXOMENOS · · Score: 5, Informative

    So...Dr. Tannenbaum's other project is Electoral-vote.com (2), an election prediction site (and one of the first). Any clue what's going to happen to that?

  10. A great writer by Anonymous Coward · · Score: 2, Interesting

    I own both "Operating Systems: Design and Implementation" and "Distributed Operating Systems". When I saw the retirement announcement, I cracked them open for the first time in many years to recall how much I learned from them.

    But my favorite of Tanenbaum's works is "Structured Computer Organization". I suppose it may be a bit dated, but I still recommend it to anyone who wants to know how computers work.

    1. Re:A great writer by TheRaven64 · · Score: 2

      I found Modern Operating Systems better than the Minix book. The Minix book tells you exactly how a toy OS works in detail. Kirk McKusick's Design and Implementation of the FreeBSD OS (new version due out in a month or two) tells you how a real modern OS works in detail. Modern Operating Systems gives you a high-level overview of how modern operating systems work and how they should work. If you want to learn about operating systems, I'd recommend reading the FreeBSD D&I book and Tanenbaum's Modern Operating Systems and skipping the Minix book (which was also a bit too heavy on code listings for my tastes).

      --
      I am TheRaven on Soylent News
  11. What I remember by Kohenkatz · · Score: 4, Interesting

    I'm sorry, but the best quote from that book is actually this one:

    Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway.

    In my networks class, we extended the calculation to a 747 full of DVDs (the best we could do at the time). Maybe one of these days, if I have a minute, I'll go back and do an A380 full of flash drives.

  12. Minix on Atari ST by sbaker · · Score: 3, Interesting

    I ran Minix for a year or more on my Atari ST - having a UNIX-like operating system on a machine I could have at home was a truly awesome thing. Tanenbaum's work is fascinating, useful and will be around for a good while...which is more or less the definition of "successful" in academic circles.

    The debates with Linus were interesting - but I always felt that they were arguing at cross-purposes. Linus wanted a quick implementation of something indistinguishable from "real UNIX" - Tanenbaum wanted something beautiful and elegant. Both got what they wanted - there was (and continues to be) no reason why they can't both continue to exist and be useful.

    Tanenbaum's statement that the computer would mostly be running one program at a time was clearly unreasonable for a PC - but think about phones or embedded controllers like BeagleBone and Raspberry Pi? Perhaps Minix is a better solution in those kinds of applications?

    --
    www.sjbaker.org
    1. Re:Minix on Atari ST by hansot · · Score: 2

      I ran Minix for a year or more on my Atari ST - having a UNIX-like operating system on a machine I could have at home was a truly awesome thing. Tanenbaum's work is fascinating, useful and will be around for a good while...which is more or less the definition of "successful" in academic circles.

      The debates with Linus were interesting - but I always felt that they were arguing at cross-purposes. Linus wanted a quick implementation of something indistinguishable from "real UNIX" - Tanenbaum wanted something beautiful and elegant. Both got what they wanted - there was (and continues to be) no reason why they can't both continue to exist and be useful.

      Tanenbaum's statement that the computer would mostly be running one program at a time was clearly unreasonable for a PC - but think about phones or embedded controllers like BeagleBone and Raspberry Pi? Perhaps Minix is a better solution in those kinds of applications?

      I'm still "using" Minix (currently 1.6.25) both on my ancient Atari 1040 ST and on an Atari ST simulator. Part out of nostalgia of course, but also to remind myself what you could do using a CPU that is about 10000 times slower than current CPU's, running an OS that you could actually understand completely by reading the complete source code. And I am using a cross compiler these days, based on GCC 4.x running on FreeBSD (see www.beastielabs.net/prerel.html) and it is amazing to see what you still can get to run on the 1993 vintage Minix, although there is still no networking.

      I remember having read the first edition of OSDI (including the source code) from cover to cover several times in the late 80's (the book split in two volumes as a consequence 8-) ) and a really learned a lot from it, although I was already heavily involved in Unix kernel hacking by then (both BSD and SVR4 based kernel ports). I still value Andy's OSDI in its several editions as a most educational experience.

    2. Re:Minix on Atari ST by gayleard · · Score: 1

      I think Minix was much better than Linux at the time - it was better written, cleaner and well-documented. I'm pretty sure Tanenbaum just got tired of the hassle of running the project. He wasn't good at collaborating with subordinates - basically, he wanted to do everything himself. One of Torvald's merits - perhaps the secret of his success - is his ability to get a team round him and share out the work - somewhat surprising since he can be so rude. In practice Tanenbaum refused to extend Minix to 386's, on the grounds that there were enough 286's (and less) in the world to fulfil the needs of Minix.

  13. Class Act by Anonymous Coward · · Score: 5, Interesting

    I remember when Microsoft paid Ken Brown throug the Alexis de Tocqueville Institution to do a hatchet job on Linus claiming that Linux was stolen from MINIX. Now Tanenbaum, who has criticized the Linux kernel design and had some spirited exchanges with Linus, could have just said nothing and let Linus fend the FUD off by himself, but instead he stepped up and did the honorable thing by decimating Brown's arguments that Linus could have come up with the Linux kernel in just a year and his competency as a researcher/writer.

    http://www.cs.vu.nl/~ast/brown/
    http://www.cs.vu.nl/~ast/brown/rebuttal/

  14. Who gives a VUCK? by tepples · · Score: 3, Funny

    They have to use "Vrije" because it was discovered that not only is the name of "Free University Compiler Kit" obscene, but it's also misleading: the software is non-free.

    1. Re:Who gives a VUCK? by Livius · · Score: 1

      What? The software is not non-denominational?

  15. Multi-spindle PCs are not uncommon by tepples · · Score: 1

    Even today there is usually one process grabbing most of the CPU time

    Yeah, the antivirus.

    in most scenarios Andy's single-threaded file system access would still serve single-user desktop machines quite well.

    Is a single-threaded file system still practical on multi-spindle PCs? These include machines with a boot SSD and a data HDD, or a boot HDD and an optical drive, or a boot HDD and an external USB SSD used for sneakernetting files too big for the available Internet connection. And by "desktop" did you mean to exclude laptops?

    1. Re:Multi-spindle PCs are not uncommon by tepples · · Score: 3, Insightful

      What's "difficult" is finding "a computer with a single mechanical hard disk drive" that stays that way for long. Desktops tend to have internal optical drives, laptops often have an internal SSD or internal or external optical drives, and both tend to often get small SSDs plugged into them.

  16. A rare proof by Murdoch5 · · Score: 1

    This is truly one of the very few profs who can talk about software design.

  17. Remembering an early 80s Tannenbaum presentation by Anonymous Coward · · Score: 2, Interesting

    In the early 80s, I did a Unix systems startup in the UK: we were an early licensee of Unix from AT&T and sold VAXen with BSD installed and supported. DEC UK hated us. DEC US happily sold us CPUs.

    In April 1983, the European Unix User's Group (EUUG), held a conference in Bonn, Germany. The speakers included Bill Joy, Sam Leffler, Steve Bourne and Andy Tanenbaum.

    It was a hugely memorable event, including Prof. Tanenbaum's presentation. We were paying AT&T $200 or so for each Unix license. Not a huge deal for a $100,000 VAX system. But, even then, many of us could see a future where Unix or something like it would run on countless devices, including cars and washing machines. In fact, when I worked for AT&T in 1984 (yes, I know, it was "a learning experience"), I was pitching exactly that to OEMs. It was clear that something cheap or free would be required. So, back in 1983, when dinosaurs ruled the Earth, Prof. Tanenbaum gave us all the seed of a thought that free (as in beer) software could change the world.

    As an aside, his presentation was a little hard to follow, but worth the effort, because his English wasn't that great. A Dutch guy sitting next to me said that his Dutch was pretty sketchy, too. I have no means to verify this but, if true, he would join a small group of my friends and acquaintances who don't speak any (human) language well. They're all engineers :-).

    I also learned that, despite Bonn being largely flooded because of heavy rains, nothing stops a Unix conference, and that the "Geoffnet" signs I saw all over the place weren't a promotion for a new network stack, but meant "Open" in German.

  18. Remembering an early 80s Tanenbaum presentation by AlexOsadzinski · · Score: 4, Interesting

    D'oh. Accidentally posted as a Coward and misspelled Prof. Tanenbaum's name. Carry on....

    In the early 80s, I did a Unix systems startup in the UK: we were an early licensee of Unix from AT&T and sold VAXen with BSD installed and supported. DEC UK hated us. DEC US happily sold us CPUs.

    In April 1983, the European Unix User's Group (EUUG), held a conference in Bonn, Germany. The speakers included Bill Joy, Sam Leffler, Steve Bourne and Andy Tanenbaum.

    It was a hugely memorable event, including Prof. Tanenbaum's presentation. We were paying AT&T $200 or so for each Unix license. Not a huge deal for a $100,000 VAX system. But, even then, many of us could see a future where Unix or something like it would run on countless devices, including cars and washing machines. In fact, when I worked for AT&T in 1984 (yes, I know, it was "a learning experience"), I was pitching exactly that to OEMs. It was clear that something cheap or free would be required. So, back in 1983, when dinosaurs ruled the Earth, Prof. Tanenbaum gave us all the seed of a thought that free (as in beer) software could change the world.

    As an aside, his presentation was a little hard to follow, but worth the effort, because his English wasn't that great. A Dutch guy sitting next to me said that his Dutch was pretty sketchy, too. I have no means to verify this but, if true, he would join a small group of my friends and acquaintances who don't speak any (human) language well. They're all engineers :-).

    I also learned that, despite Bonn being largely flooded because of heavy rains, nothing stops a Unix conference, and that the "Geoffnet" signs I saw all over the place weren't a promotion for a new network stack, but meant "Open" in German.

  19. Tannenbaum's predictions... by RyuuzakiTetsuya · · Score: 4, Interesting

    Anyone else laugh themselves stupid at some of the predictions of the future in those posts? The idea that x86 would go away and GNU/Hurd would supplant Linux...

    Predicting the future is REALLY hard.

    --
    Non impediti ratione cogitationus.
    1. Re:Tannenbaum's predictions... by LWATCDR · · Score: 3, Insightful

      X86 has gone away. Everyone is using X86-64 and Arm. I would be more Unix like systems are ARM than X86 or X86-64.. So is AMD64 X86-64 orX86/64? I can never remember.

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    2. Re:Tannenbaum's predictions... by RyuuzakiTetsuya · · Score: 2

      Yeah, for mobile, but until the last 4 years, ARM really hasn't been seen as a huge thing. Relatively speaking, this is a new development. Beyond that, x86 is *still* kicking.

      Plus there's that whole bit about GNU/Hurd being the future. :)

      --
      Non impediti ratione cogitationus.
    3. Re:Tannenbaum's predictions... by TheRaven64 · · Score: 1

      Predicting that x86 would go away was more wishful thinking than anything else. At the time, Intel had just switched from pushing the i960 to pushing the i860 and would later push Itanium as x86 replacements (their first attempt at producing a CPU that it was impossible to efficiently compile code for, the iAPX432, had already died). Given that Intel was on its second attempt to kill x86 (the 432 largely predated anyone caring seriously about x86), it wasn't hard to imagine that it would go away soon...

      --
      I am TheRaven on Soylent News
    4. Re:Tannenbaum's predictions... by MightyMartian · · Score: 1

      X86 went away fifteen years ago. Every "x86" COU built since the last 1990s runs an x86 layer, but underneath is a very different bear.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    5. Re:Tannenbaum's predictions... by LWATCDR · · Score: 1

      Mobile, Routers, NAS, and now servers. ARM is getting very big very quickly.
      In computers Attacks come from the bottom up. PC where a joke and could not hold a candle to a real computer like a PDP-11! Forget about mainframes like the 370!
      It was not HURD at the time but GNU Unix that was going to be the next big thing.
      It wasn't but hey no one is perfect.

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
  20. I read your book! by Daniel+Hoffmann · · Score: 3, Interesting

    Really, his books are quite good, I used his the operating systems book in my undergraduate classes. I honestly found reading his book more productive than going to the classes.

    1. Re:I read your book! by Daniel+Hoffmann · · Score: 1

      Same thing in Brazil...

  21. Re:Minix download fee? by TheRaven64 · · Score: 2

    Minix has been BSD licensed for well over a decade. I'm not sure exactly how long, but it was when I was an undergrad and that was a depressingly long time ago now. As the kids today say: Old troll is old.

    --
    I am TheRaven on Soylent News
  22. His other project -- electoral-vote.com by white_owl · · Score: 2

    Not only does he use polling data to do a good job of predicting the races and the control of the US Senate/House (his track record here and a comparison of his model to Nate Silver), but he has, IMHO, excellent explanations of how the campaign managers are thinking and the likely impact of political news.

    It is surprising to me that being located in Europe that he 1) cares and 2) is so wired into the US political scene. I hope he continues.

  23. At the time by nurb432 · · Score: 1

    In reality, both were correct, in their own way. You have to remember the hardware they were using in 1992. Its NOT what you have today. Not by a long shot.

    --
    ---- Booth was a patriot ----
  24. Amoeba by Jecel+Assumpcao+Jr · · Score: 2

    Interesting that he doesn't list Amoeba among his achievements. I find it far more impressive than Minix.

  25. Revisionist History: by Anonymous Coward · · Score: 1

    Much like git and a number of other design decisions along the process of Linux's development, loadable modules was a reactionary rather than proactionary development.

    You're probably too young to remember, but loadable kernel modules didn't make it in until either 1.3, or 2.1 (I'm pretty sure it was the latter since I remember having to build kernels by hand well into the 2.x days) Additionally, while not documented as such, you had to include 'stub modules' for every subsystem you wanted to be able to later compile modules for without reinstalling/rebooting the kernel. Additionally, many modules forced static values during build (didn't support plug 'n play) and thus required not only to be built on a per-system basis, but also configured for the specific hardware you had in your system. Need two of those cards in your system? Too bad.

    Many of the drivers didn't get fixed until 2.3/2.4 and it wasn't until 2.5/2.6 that most of them became truly 'plug and play' in the manner most people associate with them today.

    At the time, win9x was, on many systems, far more modular and robust in regards to handling changes in the system configuration, assuming you already had the proper drivers installed. (Linux was often better if you had supported/generic hardware for switching around, but only if lilo didn't break due to your previous bios being chs or lba and the new system being different, and didn't mind wasting a large portion of your ram at the time for the kernel and ALL drivers, which at the time could not be unloaded. I don't remember specifics but it was 8-22 megs of ram, which took forever to load and cut your usable memory size anywhere from a third to less than half.)

  26. I hope he still has a long life after retirement by petrus4 · · Score: 1

    The haters and trolls notwithstanding, Minix was a worthy accomplishment; and may yet prove more important in the future than first thought, given Red Hat's ongoing destruction of Linux.

    Professor Tanenbaum is a great man; and truthfully, I have always wished that Linus Torvalds had been kinder to him. Not all of us are necessarily meant to stand fully in the spotlight, and although perhaps both history and the debates proved Linus right, it would not have cost anything to allow the Professor to keep his dignity.

    May he have as much time with his grandchildren as he wishes; and when the time comes, an easy and joyous passing.

  27. Microkernels vs Hypervisors by unixisc · · Score: 1

    Virtualization OSs are not microkernels. Microkernels require the bulk of everything to go into userland, such as device drivers. In Hypervisors, OTOH, device drivers and a whole lot of other common resources that OSs use are packed in the kernel.

    1. Re:Microkernels vs Hypervisors by jbolden · · Score: 1

      I understand. But they are analogous. In a Hypervisor the real kernel doing most of the work is out in userland while there is a tiny "kernel" which runs part. Moreover the device drivers are split.

      Ap X uses device Y
      there is no device driver involved X uses a virtual device driver. The virtual device driver then talks to a real device. Which is pretty close to the Microkernel design.

  28. Plan 9 & Minix by unixisc · · Score: 1

    Plan 9 is an academic project? I thought it was an internal research project of Lucent/Bell Labs