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Andy Tanenbaum on 'Who Wrote Linux' 668

Andy Tanenbaum writes "Ken Brown has just released a book on open source code. In it, he claims (1) to have interviewed me, and (2) that Linus Torvalds didn't write Linux. I think Brown is batting .500, which is not bad for an amateur (for people other than Americans, Japanese, and Cubans, this is an obscure reference to baseball). Since I am one of the principals in this matter, I thought it might be useful for me to put my 2 eurocents' worth into the hopper. If you were weren't hacking much code in the 1980s, you might learn something." Tanenbaum's description of the interview process with Brown is classic. See also Slashdot's original story and Linus' reply.
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Andy Tanenbaum on 'Who Wrote Linux'

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  • by byolinux ( 535260 ) on Thursday May 20, 2004 @10:01AM (#9203459) Journal
    Torvalds Vs Tanenbaum [fluidsignal.com]. I've never used MINIX, but I believe the source code is out there somewhere, although AFAIK, it's not free software.

    I've often wondered what things will be like when Hurd is ready, and we'll have GNU and GNU/Linux, and all those BSDs, and OS X all in usage.

    And then we'll probably still have to worry about making stuff look right in IE 6, because Microsoft takes forever to update it.
  • by Anonymous Coward on Thursday May 20, 2004 @10:04AM (#9203489)
    Some Notes on the "Who wrote Linux" Kerfuffle, Release 1.1

    Background
    The history of UNIX and its various children and grandchildren has been in the news recently as a result of a book from the Alexis de Tocqueville Institution. Since I was involved in part of this history, I feel I have an obligation to set the record straight and correct some extremely serious errors. But first some background information.

    Ken Brown, President of the Alexis de Tocqueville Institution, contacted me in early March. He said he was writing a book on the history of UNIX and would like to interview me. Since I have written 15 books and have been involved in the history of UNIX in several ways, I said I was willing to help out. I have been interviewed by many people for many reasons over the years, and have been on Dutch and US TV and radio and in various newspapers and magazines, so I didn't think too much about it.

    Brown flew over to Amsterdam to interview me on 23 March 2004. Apparently I was the only reason for his coming to Europe. The interview got off to a shaky start, roughly paraphrased as follows:

    AST: "What's the Alexis de Tocqueville Institution?"
    KB: We do public policy work
    AST: A think tank, like the Rand Corporation?
    KB: Sort of
    AST: What does it do?
    KB: Issue reports and books
    AST: Who funds it?
    KB: We have multiple funding sources
    AST: Is SCO one of them? Is this about the SCO lawsuit?
    KB: We have multiple funding sources
    AST: Is Microsoft one of them?
    KB: We have multiple funding sources
    He was extremely evasive about why he was there and who was funding him. He just kept saying he was just writing a book about the history of UNIX. I asked him what he thought of Peter Salus' book, A Quarter Century of UNIX. He'd never heard of it! I mean, if you are writing a book on the history of UNIX and flying 3000 miles to interview some guy about the subject, wouldn't it make sense to at least go to amazon.com and type "history unix" in the search box, in which case Salus' book is the first hit? For $28 (and free shipping if you play your cards right) you could learn an awful lot about the material and not get any jet lag. As I sooned learned, Brown is not the sharpest knife in the drawer, but I was already suspicious. As a long-time author, I know it makes sense to at least be aware of what the competition is. He didn't bother.

    UNIX and Me
    I didn't think it odd that Brown would want to interview me about the history of UNIX. There are worse people to ask. In the late 1970s and early 1980s, I spent several summers in the UNIX group (Dept. 1127) at Bell Labs. I knew Ken Thompson, Dennis Ritchie, and the rest of the people involved in the development of UNIX. I have stayed at Rob Pike's house and Al Aho's house for extended periods of time. Dennis Ritchie, Steve Johnson, and Peter Weinberger, among others have stayed at my house in Amsterdam. Three of my Ph.D. students have worked in the UNIX group at Bell Labs and one of them is a permanent staff member now.

    Oddly enough, when I was at Bell Labs, my interest was not operating systems, although I had written one and published a paper about it (see "Software - Practice & Experience," vol. 2, pp. 109-119, 1973). My interest then was compilers, since I was the chief designer of the the Amsterdam Compiler Kit (see Commun. of the ACM, vol. 26, pp. 654-660, Sept. 1983.). I spent some time there discussing compilers with Steve Johnson, networking with Greg Chesson, writing tools with Lorinda Cherry, and book authoring with Brian Kernighan, among many others. I also became friends with the other "foreigner," there, Bjarne Stroustrup, who would later go on to design and implement C++.

    In short, although I had nothing to do with the development of the original UNIX, I knew all the people involved and much of the history quite well. Furthermore, my contact with the UNIX group at Bell Labs was not a secret; I even thanked them all for having me as a summer visitor in the preface to the first editio
  • Article text (Score:5, Informative)

    by Anonymous Coward on Thursday May 20, 2004 @10:04AM (#9203491)
    Slashdotted...
    Some Notes on the "Who wrote Linux" Kerfuffle, Release 1.1
    Background

    The history of UNIX and its various children and grandchildren has been in the news recently as a result of a book from the Alexis de Tocqueville Institution [adti.net]. Since I was involved in part of this history, I feel I have an obligation to set the record straight and correct some extremely serious errors. But first some background information.

    Ken Brown, President of the Alexis de Tocqueville Institution, contacted me in early March. He said he was writing a book on the history of UNIX and would like to interview me. Since I have written 15 books and have been involved in the history of UNIX in several ways, I said I was willing to help out. I have been interviewed by many people for many reasons over the years, and have been on Dutch and US TV and radio and in various newspapers and magazines, so I didn't think too much about it.

    Brown flew over to Amsterdam to interview me on 23 March 2004. Apparently I was the only reason for his coming to Europe. The interview got off to a shaky start, roughly paraphrased as follows:

    AST: "What's the Alexis de Tocqueville Institution?"
    KB: We do public policy work
    AST: A think tank, like the Rand Corporation?
    KB: Sort of
    AST: What does it do?
    KB: Issue reports and books
    AST: Who funds it?
    KB: We have multiple funding sources
    AST: Is SCO one of them? Is this about the SCO lawsuit?
    KB: We have multiple funding sources
    AST: Is Microsoft one of them?
    KB: We have multiple funding sources

    He was extremely evasive about why he was there and who was funding him. He just kept saying he was just writing a book about the history of UNIX. I asked him what he thought of Peter Salus' book, A Quarter Century of UNIX [amazon.com]. He'd never heard of it! I mean, if you are writing a book on the history of UNIX and flying 3000 miles to interview some guy about the subject, wouldn't it make sense to at least go to amazon.com and type "history unix" in the search box, in which case Salus' book is the first hit? For $28 (and free shipping if you play your cards right) you could learn an awful lot about the material and not get any jet lag. As I sooned learned, Brown is not the sharpest knife in the drawer, but I was already suspicious. As a long-time author, I know it makes sense to at least be aware of what the competition is. He didn't bother.

    UNIX and Me

    I didn't think it odd that Brown would want to interview me about the history of UNIX. There are worse people to ask. In the late 1970s and early 1980s, I spent several summers in the UNIX group (Dept. 1127) at Bell Labs. I knew Ken Thompson, Dennis Ritchie, and the rest of the people involved in the development of UNIX. I have stayed at Rob Pike's house and Al Aho's house for extended periods of time. Dennis Ritchie, Steve Johnson, and Peter Weinberger, among others have stayed at my house in Amsterdam. Three of my Ph.D. students have worked in the UNIX group at Bell Labs and one of them is a permanent staff member now.

    Oddly enough, when I was at Bell Labs, my interest was not operating systems, although I had written one and published a paper about it (see "Software - Practice & Experience," vol. 2, pp. 109-119, 1973). My interest then was compilers, since I was the chief designer of the the Amsterdam Compiler Kit (see Commun. of the ACM, vol. 26, pp. 654-660, Sept. 1983.). I spent some time there disc

  • by tribulation2004 ( 751416 ) on Thursday May 20, 2004 @10:04AM (#9203492)
    You'd be wary of Tannenbaum's assertion that Linus wrote Linux? Did you read his statements at all, or did you simply comment in a rush to be one of the first posters?
  • by madprof ( 4723 ) on Thursday May 20, 2004 @10:04AM (#9203494)
    MINIX is licensed under the BSD licence, as mentioned in the article.
  • by Anonymous Coward on Thursday May 20, 2004 @10:07AM (#9203519)
    ...and to make them perform reasonably well, both of these have hacks (server collocation, etc.) that remove the whole reason for microkernels in the first place.

    Don't fall for the hype.

    On the other hand, QNX is actually pretty true to the concept.
  • In a kernel there is a lot of interaction between the various parts. In a monolithic kernel these interactions are performed by simple subroutine calls and manipulation of shared data. In a microkernel these interactions require a more complex switch between tasks, and message passing. In exchange, you get better protection of one part from the others, which makes tracking down bugs quicker.
    John Sauter (J_Sauter@Empire.Net)
  • On Minux (Score:5, Informative)

    by Gumshoe ( 191490 ) on Thursday May 20, 2004 @10:10AM (#9203569) Journal
    On Minix:
    While [Minix is] not free software in the sense of "free beer" it was free software in the sense of "free speech" since all the source code was available for only slightly more than the manufacturing cost.
    That's not "free as in speech". IIRC, the licence prevented us from distributing changes to the OS in any form other than patch files. This was a major reason why people became interested in Linux -- no such restriction exists and it is therefore, truly "free as in speech".
  • Mirror here (Score:2, Informative)

    by Brent Nordquist ( 11533 ) <bjnord.gmail@com> on Thursday May 20, 2004 @10:12AM (#9203580) Homepage
    The whole thread was linked from Groklaw yesterday at this URL [educ.umu.se].
  • by Anonymous Coward on Thursday May 20, 2004 @10:12AM (#9203590)
    From Micro Kernels [cornell.edu]

    The basic idea of microkernels is to minimize the kernel, and implement as much of it as possible outside the TCB. The kernel should only export simple, low-level operations which hopefully allow for more efficient application implementations. This idea dates back to [Hansen 70], and a good overview can be found in [Liedtke 96]. Traditionally kernels are 'monolithic' in the sense that they implement all their functionality in a relatively unstructured fashion within the TCB. The advantages of microkernels are obvious from a software engineering standpoint:

    The TCB is made smaller, reducing the chances of errors due to its faulty implementation. The OS is more modular and thus more flexible and extensible.

    Services previously in the TCB can now possibly have more than one different implementation, perhaps even running concurrently.

    Microkernels initially met with great enthusiasm and in the late 80s there was much work on them in both academic and commercial settings. This wave of initial enthusiasm subsided when people started encountering what seemed to be inherent difficulties with the flexibility and efficiency of microkernel implementations:

    For some frequent operations, e.g. networking, the overhead of context-switching was too great for an out-of-kernel implementation. Thus the microkernels were not as efficient as originally thought.

    There are great difficulties with supporting more than one implementation of a basic system service, especially when more than one is to run concurrently. Thus the microkernels were not nearly as flexible as supposed.

    These difficulties were overcome by various compromises to the original microkernel ideals. Several efficiency-critical features were brought back into the kernel and the addition of new features into the kernel was supported through downloadable binary code, or trusted 'kernel-loaded modules'.

    But this integration of most drivers and servers back into the TCB largely eliminates the benefits of the microkernel approach, in the end resulting in an even more complex monolithic-like OS kernel.

  • Obscure Reference (Score:1, Informative)

    by Anonymous Coward on Thursday May 20, 2004 @10:16AM (#9203621)
    You could include Mexicans and most of the countries in the caribean. I don't think baseball is popular anywhere else in the world.
  • Obligatory mirror (Score:4, Informative)

    by TaxSlave ( 23295 ) <<lockjaw> <at> <lockjawslair.com>> on Thursday May 20, 2004 @10:20AM (#9203648) Homepage Journal

    Here's a mirror [lockjawslair.com] of the article while it lasts.

  • by bbh ( 210459 ) on Thursday May 20, 2004 @10:30AM (#9203737)
    It means of his two claims, half (%50) of them are correct. The two claims are that Brown interviewed Tanenbaum (true) and that Linus Torvalds didn't write Linux (false).

    bbh
  • by jmitchel!jmitchel.co ( 254506 ) on Thursday May 20, 2004 @10:30AM (#9203739)
    AST lists several independently developed systems of equivalent complexity to Mixix 1.0 / System 7. Here are a couple more I found:

    OMU (6809 processor, ported to 68000) roughly system 7 but only single user, integrated shell.
    http://tallyho.bc.nu/~steve/omu.html

    UZI (Z80 processor, ported to 180, 280) roughly system 7: multitasking
    http://www.dougbraun.com/uzi.html
  • Re:Oh the irony. (Score:2, Informative)

    by Anonymous Coward on Thursday May 20, 2004 @10:31AM (#9203744)
    Quote:

    "Oh everything's stolen nowdays. Why the fax machine is nothing but a waffle iron with a phone attached."
  • Btw. I forgot (Score:2, Informative)

    by MemoryDragon ( 544441 ) on Thursday May 20, 2004 @10:31AM (#9203752)
    http://os.inf.tu-dresden.de/L4/LinuxOnL4/index.sht ml Is an example of a Linux personality running on a mikrokernel architecture. I havent had a look at it, but the developers claim only a performance penalty of 4% to the monolithic makro kernel standard Linux has.
  • by Quill_28 ( 553921 ) on Thursday May 20, 2004 @10:39AM (#9203834) Journal
    In baseball anything over .300(30%) is considered excellent when it comes to hitting.

    So to say you are batting(hitting) five hundred means you were successful half the time.

  • by mojoNYC ( 595906 ) on Thursday May 20, 2004 @10:39AM (#9203839) Homepage
    my first reaction to this attack was, 'who the f### is Ken Brown? as they taught me back in school, 'always consider the source' --if this guy's attacking Linux, he'd better have some solid credentials in the computer industry, right? well, all it took was a Google search, and the first link I hit told me all i need to know: Anti-Open Source lobbyists need love, too Friday October 25, 2002 - [ 03:00 PM GMT ] Topics: Migration - By Robin "Roblimo" Miller - I felt bad for Ken Brown of the Alexis De Toqueville Institution (AdTI) last week... http://www.newsforge.com/business/02/10/25/056218. shtml?tid=19 thanks to Roblimo, we have a first-hand account of Ken Brown's shameless FUD-ing, back in 2002--read this link for a cuttingly funny look at Mr. Browns earlier efforts;> you gotta love the 'thousands of eyeballs' that are working on our side--it more than offsets what M$ gets from spreading it's dirty money around... -DWitt ps. methinks Brown's IP has just gone down the tubes--thank you very much Andy Tanenbaum!
  • by adamofgreyskull ( 640712 ) on Thursday May 20, 2004 @10:40AM (#9203865)
    I especially loved the comment that insinuates that Linus could have done a better job if he HAD stolen the code, than he did.
    AST is talking about the design, but Linus has made similar comments regarding certain parts of the implementation [groklaw.net] to refute SCO's claims:
    Basically, the above is _exactly_ the kinds of mistakes a young programmer would make. It's classic.
  • Re:QNX (Score:5, Informative)

    by RAMMS+EIN ( 578166 ) on Thursday May 20, 2004 @10:43AM (#9203892) Homepage Journal
    However, L4Linux is Linux running atop an L4 kernel. This means that the Linux kernel is still as monolithic as it always was. The same goes for MkLinux (Linux on Mach) and Darwin (a monolithic BSD server on Mach).
  • by B'Trey ( 111263 ) on Thursday May 20, 2004 @10:46AM (#9203913)
    I read the article from the Groklaw link before it showed up on /. Tanenbaum says that at least five different people single handedly wrote a UNIX-like kernel and that Linus clearly wrote Linux. He also says that Brown, the person who interviewed him, was completely clueless and obviously pushing an agenda.

    The bitter part comes in the last couple of paragraphs, where he takes the opportunity to say that Linus was a misguided kid who should have paid more attention in class such that he would have seen the obvious superiority of a microkernel over a macrokernel. But he's quick to point out that he and Linus are not enemies.

  • by Sunda666 ( 146299 ) on Thursday May 20, 2004 @10:48AM (#9203932) Homepage
    Windoz had a microkernel in the NT 3.51 days. It is way far from a microkernel today. There are some info about this on the NT 4 resource kit documentation.

    cheers.
  • by CustomDesigned ( 250089 ) <stuart@gathman.org> on Thursday May 20, 2004 @10:50AM (#9203944) Homepage Journal
    Exokernels reinvent IBMs VM system. "An Exokernel securely multiplexes the raw hardware, and application libraries directly implement traditional OS functions." This does not mean that applications must now include their own drivers for every possible hardware they might use. It means that drivers can now be packaged as shared libraries in user space rather than as kernel modules.

    To summarize, let me call the part that securely multiplexes hardware the "kernel".

    • Monolithic makes drivers share address space with the "kernel".
    • With Microkernel, "kernel", drivers, filesystems, applications, etc each get their own address spaces.
    • Exokernel makes drivers share address space with applications. (Hopefully, filesystems get their own process and address space.)
    As you can see, as soon as you start partitioning applications into separate processes for security and robustness, the distinction between Exokernel and Microkernel becomes rather vague. The advantage of the Exokernel or VM approach is that you get the flexibility of keeping things like filesystems in a separate process for security and robustness, and things like video drivers in the same address space for performance. You might even have an X server as a separate process, but still allow full screen mode games that directly call the driver libraries for performance.

    IBM's VM was never that popular in its raw "Exokernel" mode with drivers in application space. However, it is still hugely popular as a way to run multiple Operating Systems as the "applications". Your mainframe can securely run multiple instances of S/390 Linux and traditional mainframe systems together.

  • by Zocalo ( 252965 ) on Thursday May 20, 2004 @10:50AM (#9203951) Homepage
    Matt Loney of ZDNet UK is covering the story, including Andy Tanenbaum's two Euro-cents here [zdnet.co.uk]. I don't think anyone at AdTI, least of all Ken Brown, is going to be living off royalties any time soon - "falls at the starting gate" indeed. ZD even mention AdTI's ties to Microsoft least there be any doubt, which is nice of them. :)
  • by ReinoutS ( 1919 ) <reinout&gmail,com> on Thursday May 20, 2004 @10:58AM (#9204011) Homepage
    It's a Christian holiday, "Hemelvaart". It's 40 days after Easter, the day Jesus supposedly ascended to Heaven on a cloud.

    BTW I'm a student at cs.vu.nl and I can tell you the bandwidth is definately not the problem (we're almost directly connected to the Amsterdam-US backbone).
  • by mst76 ( 629405 ) on Thursday May 20, 2004 @10:58AM (#9204015)
    > MINIX is licensed under the BSD licence, as mentioned in the article.

    Not until 2000, when Prentice Hall finally came to realize that nobody would pay for Minix with Linux and the BSDs out there.
  • You appear to misunderstand what a virtual machine is. The BSD kernel in OS X is 100% native code, running 100% in concert with the rest of the system. "Virtual Machine" implies that you are attempting to fool software into believing that it is running on hardware (real or imagined) that it isn't.

    Instead, the BSD layer of Mac OS X simply provides a POSIX interface to programs. "Kernel calls" are captured in the BSD kernel server, but are routed to the proper Mach server instead of being routed to the driver or I/O area of a full BSD kernel. Depending on how this is implemented, it could have a very minimal impact on performance. Even if it does slow things down in the processor, programs spend 90% of their time blocking on hardware anyway.
  • by Waffle Iron ( 339739 ) on Thursday May 20, 2004 @11:01AM (#9204056)
    So what's Windows? Micro? Monolithic? Neither?

    DOS, Win3.1, 95, 98, Me are all super-monolithic. Your copy of Minesweeper.exe runs in the same space as everything else and essentially becomes part of the kernel.

    NT 3.51 was a fairly pure microkernel implementation. However, it had some performance issues, so Microsoft moved a few things like the graphics drivers back into the kernel for later versions of NT, Win2K and WinXP. Modern versions of Windows are thus a kind of hybrid.

  • by jake_eck ( 711007 ) on Thursday May 20, 2004 @11:08AM (#9204106)
    What does this quote reference? "Some of you may find it odd that I am defending Linus here. After all, he and I had a fairly public "debate" some years back. My primary concern here is getting trying to get the truth out and not blame everything on some teenage girl from the back hills of West Virginia."

    I thought it was a reference to Lindie England.
  • by eggboard ( 315140 ) * on Thursday May 20, 2004 @11:10AM (#9204130) Homepage
    The teenage girl is a reference to the smiling, cigarette-smoking woman Lynndie England pictured pointing at a humiliated Iraqi man's genitals, and the fact that she and her smiling comrades will take the fall for Donald Rumsfeld and the rest of the chain of command.
  • Re:On Minux (Score:3, Informative)

    by rthille ( 8526 ) <web-slashdot@@@rangat...org> on Thursday May 20, 2004 @11:13AM (#9204159) Homepage Journal
    That's exactly "free as in speech". If I give a speech at a gathering and you write it all down and start distributing it, you're violating my copyright. However, if you distribute a patch set to my speech because you feel it reads better with your modifications, then you're welcome to do so.
  • by Jeremy Erwin ( 2054 ) on Thursday May 20, 2004 @11:13AM (#9204161) Journal
    One reason that Minix did not "rise to the challenge" is that Tannenbaum wanted to keep his OS simple, for didactic reasons. Linux designed his OS to run on his new 386 computer, which had all sorts of nifty capabilities-- memory protection, a 32 bit address space, etc. Tannenbaum thought it was important to run run on on low end (student) hardware
  • Re:OS X (Score:2, Informative)

    by rizzy ( 24400 ) on Thursday May 20, 2004 @11:15AM (#9204185)
    A lot of the message-passing is therefore avoided; and the performance costs that those message passes would incur.

    Crap, if Apple has taken measures to improve the Darwin kernel performance, then I would submit that they have failed miserably.


    Since we're talking kernels here, I don't feel bad bringing out lmbench numbers. here [terizla.org] and here [terizla.org]are lmbench runs on the same hardware comparing linux to Darwin. The Linux kernel kicks the crap out of the Darwin kernel, in most cases by an order of magnitude.

  • by Sajarak ( 556353 ) on Thursday May 20, 2004 @11:19AM (#9204232) Homepage
    but Linux rose to the challenge, Minix pretty much didn't.

    To be fair though, he primarily wrote Minix for educational purposes, with the idea that a computer science student could read and understand the entire system within the duration of a one-semester course. He refused to add a lot of features which would have made Minix harder to understand, even though they would have made it more useful.

  • by Anonymous Coward on Thursday May 20, 2004 @11:19AM (#9204243)
    both.
  • Re:Article text (Score:1, Informative)

    by n0ano ( 148272 ) <n0ano@arrl.net> on Thursday May 20, 2004 @11:20AM (#9204256) Homepage
    With all the security problems Windows has now, it is increasingly obvious to everyone that tiny microkernels, like that of MINIX, are a better base for operating systems than huge monolithic systems.


    Interesting comment from AST given that, to my knowledge, Windows IS a micro-kernel based OS and it is still the most insecure system out there. If micro-kernel architectures were so inherently secure then Windows would have one of the best records in the business.


    I'm sorry Andy but, in a University teaching environment, I agree with you, a micro-kernel is the way to go. It makes it much easier to have students try different algorithms and see how they affect the system if the memory management system is done as a user process.


    Having said that, for a production system a micro-kernel is just wrong. The stability and security of a monolithic kernel is much more important than the flexibility of a micro-kernel.

  • by Fnkmaster ( 89084 ) on Thursday May 20, 2004 @11:21AM (#9204271)
    From what I've observed there are lots of programming projects that are "hard" for companies and large organizations because they aren't so amenable to "early partition" as people would like, and yet are substantially easier for one developer (or two in some cases) who partition the problem using internal divide-and-conquer, thus completely understanding the partitioning scheme right off the bat rather than spending months hashing it out at meetings and miscued early development efforts.


    I had an experience where an entire development team of twenty people spent about a year and a half writing a large, grandiose enterprise software system that was supposed to be general-purpose and flexible, but in the end was a real performance turd at the job it was supposed to do. Using what I knew about the actual problem from looking at the previous solution's mistakes and the original problem statement, I rewrote the system from scratch over about 8 weeks at a client's site, averaging about 300 SLOCs a day (coding in Java where I can fly), with one developer helping me on a few specific tasks, and we ended up with a system that was functionally equivalent and about 50 times faster than the previous version because it stripped out all the unnecessary modularity (modularity is good, but if you split something that should be one component into ten, you just get lots of extra overhead) and message-passing that gunked up the original design.


    I can't help but think of the analogy between this project and the Linux/MINIX effort. My knowledge of the problem was informed by analyzing the earlier design, but not a line of code was actually derived from it. And the twenty-some-odd man year effort was replaced neatly by a 3-man-month effort that was superior.


    The moral of the story is that any of us who've been around in the software world long enough will tell you that most any system, assuming you lift all the crazy featurization constraints, can be written fairly rapidly by one person. And that usually you'll get a better result with an early working product and iterative functionality development than you will with a monolithic development effort, assuming you know the architectural parameters going into the effort by having been able to analyze previous efforts at solving a similar problem.


    So the point is... keep the assumptions in mind before you start estimating a project's size and scope, man-hour requirements and so on. Development of UNIX-like OSes was a well-defined, well-understood problem at the time Linus did his work. And don't go claiming that somebody accomplished an impossible task unless you have a REALLY good understanding of the software engineering process in general, and the particulars of the problem they solved - in this case Ken Brown has neither. We didn't really need Mr. Tanenbaum to tell us that, but it shows what a stand-up guy he is that he has made a clear effort to defend Linus despite any past arguments they may have had.

  • No. (Score:2, Informative)

    by Anonymous Coward on Thursday May 20, 2004 @11:32AM (#9204394)
    No. No he didn't.

    Read more history.

    More importantly, he didn't "invent" basic, he stole it from http://inventors.about.com/library/inventors/blbas ic.htm

    Dartmouth.

    That's a more interesting question is it not? That Bill Gates and Paul Allen stole Basic from Dartmouth?
  • Article text (Score:0, Informative)

    by Anonymous Coward on Thursday May 20, 2004 @11:40AM (#9204484)
    Background

    The history of UNIX and its various children and grandchildren has been in the news recently as a result of a book from the Alexis de Tocqueville Institution. Since I was involved in part of this history, I feel I have an obligation to set the record straight and correct some extremely serious errors. But first some background information.

    Ken Brown, President of the Alexis de Tocqueville Institution, contacted me in early March. He said he was writing a book on the history of UNIX and would like to interview me. Since I have written 15 books and have been involved in the history of UNIX in several ways, I said I was willing to help out. I have been interviewed by many people for many reasons over the years, and have been on Dutch and US TV and radio and in various newspapers and magazines, so I didn't think too much about it.

    Brown flew over to Amsterdam to interview me on 23 March 2004. Apparently I was the only reason for his coming to Europe. The interview got off to a shaky start, roughly paraphrased as follows:

    AST: "What's the Alexis de Tocqueville Institution?"
    KB: We do public policy work
    AST: A think tank, like the Rand Corporation?
    KB: Sort of
    AST: What does it do?
    KB: Issue reports and books
    AST: Who funds it?
    KB: We have multiple funding sources
    AST: Is SCO one of them? Is this about the SCO lawsuit?
    KB: We have multiple funding sources
    AST: Is Microsoft one of them?
    KB: We have multiple funding sources

    He was extremely evasive about why he was there and who was funding him. He just kept saying he was just writing a book about the history of UNIX. I asked him what he thought of Peter Salus' book, A Quarter Century of UNIX. He'd never heard of it! I mean, if you are writing a book on the history of UNIX and flying 3000 miles to interview some guy about the subject, wouldn't it make sense to at least go to amazon.com and type "history unix" in the search box, in which case Salus' book is the first hit? For $28 (and free shipping if you play your cards right) you could learn an awful lot about the material and not get any jet lag. As I sooned learned, Brown is not the sharpest knife in the drawer, but I was already suspicious. As a long-time author, I know it makes sense to at least be aware of what the competition is. He didn't bother.
    UNIX and Me

    I didn't think it odd that Brown would want to interview me about the history of UNIX. There are worse people to ask. In the late 1970s and early 1980s, I spent several summers in the UNIX group (Dept. 1127) at Bell Labs. I knew Ken Thompson, Dennis Ritchie, and the rest of the people involved in the development of UNIX. I have stayed at Rob Pike's house and Al Aho's house for extended periods of time. Dennis Ritchie, Steve Johnson, and Peter Weinberger, among others have stayed at my house in Amsterdam. Three of my Ph.D. students have worked in the UNIX group at Bell Labs and one of them is a permanent staff member now.

    Oddly enough, when I was at Bell Labs, my interest was not operating systems, although I had written one and published a paper about it (see "Software - Practice & Experience," vol. 2, pp. 109-119, 1973). My interest then was compilers, since I was the chief designer of the the Amsterdam Compiler Kit (see Commun. of the ACM, vol. 26, pp. 654-660, Sept. 1983.). I spent some time there discussing compilers with Steve Johnson, networking with Greg Chesson, writing tools with Lorinda Cherry, and book authoring with Brian Kernighan, among many others. I also became friends with the other "foreigner," there, Bjarne Stroustrup, who would later go on to design and implement C++.

    In short, although I had nothing to do with the development of the original UNIX, I knew all the people involved and much of the history quite well. Furthermore, my contact with the UNIX group at Bell Labs was not a secret; I even thanked them all for having me as a summer visitor in the preface to the first edition of my book Computer Networks. Amazingly, Brown knew not
  • Re:Oh the irony. (Score:5, Informative)

    by advocate_one ( 662832 ) on Thursday May 20, 2004 @11:46AM (#9204541)
    yes... it's amazing what he managed to write with the help of a wodge of printout from a garbage can [salon.com]... (requires sub or day pass)
    Bricklin sent waves of laughter through the auditorium by reading a passage from Lammers' interview with Bill Gates in which the young Microsoft founder explained that his work on different versions of Microsoft's BASIC compiler was shaped by looking at how other programmers had gone about the same task. Gates went on to say that young programmers don't need computer science degrees:
    "The best way to prepare is to write programs, and to study great programs that other people have written. In my case, I went to the garbage cans at the Computer Science Center and I fished out listings of their operating systems."[my emphasis]

    Bricklin finished reading Gates' words and announced, with an impish smile, "This is where Gates and [Richard] Stallman agree!"

    The "Programmers at Work" panelists were full of optimism about new opportunities to reinvent software -- in the mobile-phone world (where, Scott Kim noted, the constraints of small screens and tiny memory made it feel "like the early days" again), in the new universe of RF tags, and in the still-unfolding saga of global networking. Bob Carr reminded everyone that technology transformations usually take 20 years to unfold -- "I remember thinking in 1987 that the PC industry was mature, it was over" -- and that the Internet is only halfway through that cycle.

    Still, that picture of Bill Gates dumpster-diving for operating-system code was hard to shake. Finding new ways to think about programming and to make better software demands a willingness for pioneers to open up their work so others can learn from it. "Getting the software industry on a more open, fair and level playing field," as Hertzfeld put it, is a prerequisite for any leap forward in the programming world. Software patents are a looming train wreck; competition in most "end-user" software is largely a distant memory. Simonyi's technical bottleneck is also a social, political and business logjam.
    Linus of course was doing a course at Uni with Tannenbaum's Minix as it's example code... But then again... he didn't deliberately set out to write an OS from scratch... to begin with, he wrote it primarily to have fun with the 386 instruction set and also to read usenet...
  • by aug24 ( 38229 ) on Thursday May 20, 2004 @11:48AM (#9204584) Homepage

    Interesting...! I think I'll email PJ with this little lot!

    J.

  • MINIX "nice" command (Score:3, Informative)

    by maitas ( 98290 ) on Thursday May 20, 2004 @11:50AM (#9204626) Homepage

    In fact, back at university I implemented the "nice" command for MINIX 2.0. The hard part was to pass the message from userland to the scheduler (which previosly I had modified so it sorts the process qeue according to the priority).
    I haven't try anything similar for Linux, but having a monolitic architecture surely simplifies the message passing burden (which was a lot!), although it migth add other problems I haven't consider...

    For a start, the simplest OS seems to be a monolitic approach, single-task, single-user, like DOS... taking to the extreme the KISS approach we would go back to pure assembly language...
  • Mirror (Score:5, Informative)

    by Door-opening Fascist ( 534466 ) <skylar@cs.earlham.edu> on Thursday May 20, 2004 @11:54AM (#9204671) Homepage
    Looks like the server is bogged down. Here's a couple mirrors:

    Mirror #1 [earlham.edu]

    Mirror #2 [dhs.org]

  • Re:Don't forget BeOS (Score:3, Informative)

    by chrish ( 4714 ) on Thursday May 20, 2004 @11:58AM (#9204740) Homepage
    BeOS did not have a microkernel, although it did borrow some ideas from microkernel design. Filesystems, drivers, etc. were loaded into the kernel at boot time, they weren't separate processes.
  • by Anonymous Coward on Thursday May 20, 2004 @11:58AM (#9204743)
    If you do a Google search for MINUX, it says:
    Did you mean: LINUX I am sure that makes Tanenbaum happy.


    Dumbass. Next time try typing in the correct name, MINIX not minux.
  • Which challenge? (Score:4, Informative)

    by StrawberryFrog ( 67065 ) on Thursday May 20, 2004 @11:59AM (#9204753) Homepage Journal
    but Linux rose to the challenge, Minix pretty much didn't.

    RTA. particularly the bit where Tanenbaum says that he kept MINIX small in order to to keep it up the challenge of being a good teaching tool. And then goes on to imply that he was suprised that it took so long for the niche of free, open production-featured UNIX to be filled by Linux and BSD.

    Of course, Tanenbaum would have prefered that niche to be filled by a microkernel OS, but MINIX was never going to be that OS. MINIX was going to be the code that the creators of free UNIX cut thier teeth on at university. And guess what, it was.
  • by zulux ( 112259 ) on Thursday May 20, 2004 @12:04PM (#9204834) Homepage Journal


    Microware OS-9 should be in there - it's UNIX like, in that it can do everything UNIX can do....

    Came out atoun '84 if I remember correctly - Multitasking, Multi user - with an add on multiple windowed graphical shell.

    OS-9 is still used in a lot of set-top-boxes and was used be Phillips's CD-i

  • by Pac ( 9516 ) <paulo...candido@@@gmail...com> on Thursday May 20, 2004 @12:07PM (#9204866)
    It is a shame that such a bunch of liers, obviously finnanced by the Microsoft Marketing Department, is allowed to use Tocqueville's name. The man must be almost rising from his grave to do them justice.

    Anyway, a quote of his seems to apply:"In order to enjoy the inestimable benefits that the liberty of the press ensures, it is necessary to submit to the inevitable evils it creates..."

    All is pretty clear: the Alexis de Tocqueville Foundation is nothing more than a front-end to third-party interests, the Foundation agenda is clearly determined by the ammount of money payed by its clients and the Foundantion and its members are willing to say and do anything, no matter how dishonnest, to please their clients.

    It is now just a matter using every opportunity to show the evidence to the press so the harm they can do is minimized. Until Microsoft chooses another "Foundation" to fund...
  • by Anonymous Coward on Thursday May 20, 2004 @12:15PM (#9204981)
    He is telling that Linux was 2x faster on *that very hardware*.

    Who's the bunch of crap now?
  • plot thickens indeed (Score:2, Informative)

    by mardoen ( 557915 ) on Thursday May 20, 2004 @12:20PM (#9205040) Homepage

    Ha. A search for the author of this posting [google.com] reveals a rather lengthy list of "OS Research Questions" in forums, newsgroups and alike. Implementation details, amount of work, authors and ownership, etc.

    But shouldn't come as a surprise, as his email address "[name]@adti.net" belongs to the Alexis de Tocqueville Institution mentioned in the article.

  • by Anonymous Coward on Thursday May 20, 2004 @12:26PM (#9205118)
    The link of the OP:
    Anti-Open Source lobbyists need love, too [newsforge.com]
  • by Anonymous Coward on Thursday May 20, 2004 @12:27PM (#9205134)
    NT 4.0 moved away from microkernel by putting window management and graphics subsystem into the kernel. It was because of performance measurements done at the time on the hardware that existed at the time. Unfortunately these measurements were a snapshot in time - hardware became much more powerful and over time proved moving the gui subsystem into the kernel was shortsighted and unnecessary.
  • by Jeremy Erwin ( 2054 ) on Thursday May 20, 2004 @12:27PM (#9205140) Journal
    Minix ran on 8086 computers. 20 bit memory. No memory protection.

    I still remember reading in Byte about the first 486 machine-- a rather expensive, bulky system, too exotic for personal use. After a few months, more economical systems were gradually introduced. It was a far cry from today's market, where the usual response to a new x86 incarnation is to benchmark it against "Serious Sam" and "Quake 3".
  • Ken Brown (Score:2, Informative)

    by Anonymous Coward on Thursday May 20, 2004 @12:36PM (#9205278)
    In case you have any questions about his book, Ken Brown can be found here [mailto] or here [mailto]. (Source [digital-law.net].)
  • Re:QNX (Score:5, Informative)

    by TheRaven64 ( 641858 ) on Thursday May 20, 2004 @12:47PM (#9205415) Journal
    As for Darwin; it was certainly slow on my x86 laptop, but it's not lacking any speed on my iBook. I guess that says something about the quality of the x86 port (hint: there is no such thing).

    The performance hit of doing a context switch on PowerPC is about the same as doing a function call, which make multithreading and things like microkernels very easy to do fast. On x86, the overhead is often an order of magnitude larger, making microkernels crawl.

  • by Anonymous Coward on Thursday May 20, 2004 @12:47PM (#9205417)
    What do we know about Justin Orndorff

    1. On April 12, 2004, he asked about Linux ownership on usenet linux.kernel, using IP address 66.44.2.45 (RCN dialup access range). He used raison__d_etre@hotmail.com as his originating email address.
    References :
    http://groups.google.com/groups?selm=1Kbes-3hM- 1%4 0gated-at.bofh.it&output=gplain

    2. On April 28, 2004, he asked about obtaining older versions of Minix in a Minix related mailing-list. He used raison__d_etre@HOTMAIL.COM as his originating email address.
    References :
    http://listserv.nodak.edu/scripts/wa.exe?A2=ind 040 4d&L=minix-l&F=&S=&P=59

    3. On May 6, 2004, he posted questions about O.S. development on usenet alt.os.development, using IP address 66.44.4.15 (again, RCN dialup access range). He used jorndorff@adti.net as his originating email address.
    References :
    http://groups.google.com/groups?selm=b6920e1.04 050 61039.75c2fc2c%40posting.google.com&output=gplain)

    4. Later on May 6, 2004, the very same questions were asked in various web forums by someone using the nickname "jnana".
    References :
    http://www.webmasterworld.com/forum40/1067.htm
    http://forums.devhardware.com/showthread.php?t=18 1 19&goto=nextoldest
    http://www.osdev.org/board.jsp ?message=6907

    5. On may 18th, 2004, he asked questions about corporate contribution into Linux on usenet linux.samba, using IP address 138.88.144.59 (Verizon DSL access range). He used raison__d_etre@hotmail.com as his originating email address.
    References :
    http://groups.google.com/groups?selm=1Xf0Z-7VF- 11% 40gated-at.bofh.it&output=gplain

    It is very likely that it is indeed only one person as :
    - The topics are closely related.
    - The IP used when posting using the @adti.net address (3) is on the same range as the one used when posting using the @hotmail.com address (1).
    - The questions asked using the jnana nickname (4) are the same as the ones asked using the @adti.net address (3).

    Obviously, we have someone here, going by the names of Justin Orndorff/Jnana/Raison__d_etre (French for "reason to exist, or reason to be), and who seems very interested in Linux and other FOSS intelectual properties issues.

    This person has at least two email addresses :
    raison__d_etre@hotmail.com
    jorndorff@adti.net

    What else ?

    6. He apparently has a page/blog on Devianart. He uses the same Justin O. and Jnana names. He says he's 22 and lives in CP (?), Maryland. He has apparently started a new job on March 1st.
    References :
    http://jnana.deviantart.com/
    http://jnana.devi antart.com/journal/

    7. He seems to like movies, particularly the "poetic" genre.
    References :
    http://www.amazon.com/exec/obidos/tg/cm/member- gui des/-/A17FKWGJYHSEL2/103-1166439-6115864

    8. He likes VHS music tapes trading (particularly black metal), has an email address @wam.umd.edu (University of Maryland) where he seems to be a student.
    References :
    http://www.tapetradernetwork.com/Framed_body_ri ght .asp?ArtistID=3338
    http://www.tapetradernetwork.c om/Framed_Trader_Det ail.asp?ID=9856

    9. A while back he was looking for "Codreanu comp. ['Fidelis Legio']" (whatever that is, apparently more black metal).
    References :
    http://grumblesmurf.net/pipermail/coldmeat-l/20 02- February/010935.html

    10. Well, he actually seems to be an English student at U. of Maryland (College Park, CP again, see (6)), and interested in films production.
    References :
    http://cinemaminima.com/blogs/orndorff/

    OK, so maybe this is going a little fast but we apparently have an :
    - English student in Maryland,
    - Interested in films
    - Using email addresses raison__d_etre@hotmail.com, jorndorff@adti.net and maybe morpheus@wam.umd.edu (fake ?)
    - Working since March or April for the ADTI (A. de Tocqueville Institute)
  • Re:On second thought (Score:5, Informative)

    by 0racle ( 667029 ) on Thursday May 20, 2004 @01:01PM (#9205576)
    Actually its RMS who calls Linus 'just an engineer' and its not a compliment. Its said in the vein of 'just a child,' as in he might be able to do something but he doesn't understand the ramifications. In this case, Linus isn't fighting his (RMS) holy war so he doesn't think highly of Linus and derides him as just an engineer who doesn't understand the whys of the GPL.

    A closer quote from Revolution OS is "he calls me just an engineer."
  • Re:Malicious intent (Score:5, Informative)

    by bstadil ( 7110 ) on Thursday May 20, 2004 @01:18PM (#9205837) Homepage
    Well they tried this crap two years ago at the behest of Microsoft. The article was so bad that it was pulled after just one day. Look here [parrhesia.com] for a copy, captured before it was pulled..
  • Re:OS X (Score:4, Informative)

    by tverbeek ( 457094 ) on Thursday May 20, 2004 @01:33PM (#9206070) Homepage
    The software that Apple is referring to with the term "BSD subsystem", and the BSD core I/O routines to which the grandparent is referring, are not the same thing. I don't know for sure, but I believe Apple's talking about some additional libraries and such that folks developing for BSD are used to having installed, but which aren't needed by OS X and typical Apple-centric apps.
  • by LO0G ( 606364 ) on Thursday May 20, 2004 @01:48PM (#9206270)
    Um. NT4's still got the same kernel architecture that NT3 had.

    The only difference is that in NT 4, the GDI and USER components were moved from user mode (in CSRSS.EXE) to kernel mode (as the Win32K.Sys device driver).

    Having the GUI running at ring 0 is not the same thing as having a monolithic kernel.
  • by Sunda666 ( 146299 ) on Thursday May 20, 2004 @01:52PM (#9206350) Homepage
    but it a'int a microkernel either, eh? (think QNX).

    cheers.
  • Re:QNX (Score:4, Informative)

    by RAMMS+EIN ( 578166 ) on Thursday May 20, 2004 @01:59PM (#9206447) Homepage Journal
    Exactly. The parent probably meant disk device driver. I wonder what blocksize he used? Picking the right blocksize makes all the difference in the world; larger blocksizes reduce head movements (which are orders of magnitude slower than actual data transfers), but will eventually exhaust core memory.
  • From CNet Review (Score:3, Informative)

    by gordguide ( 307383 ) on Thursday May 20, 2004 @03:26PM (#9207669)
    " Microsoft indeed has provided funding to the Alexis de Tocqueville Institution for five years, a Microsoft representative said, without disclosing how much has been granted. Microsoft funds several public policy institutes, including the American Enterprise Institute, the Center for Strategic and International Studies, the Heritage Foundation, and the Cato Institute, the representative said. "

    CNet [com.com]
  • by Anonymous Coward on Thursday May 20, 2004 @03:39PM (#9207827)
    Um, but it is compiling for different instruction sets, which is a different task.

    Perhaps if you were cross-compiling for intel on the mac the number comparison would mean something.
  • by cyb97 ( 520582 ) * <cyb97@noxtension.com> on Thursday May 20, 2004 @03:50PM (#9207978) Homepage Journal
    but who says gcc is equally efficient on both PPC and x86?
    It might be for all I know, but it's certainly more likely that it's gcc being a troll rather that the actual mach kernel being slow...
  • by EddWo ( 180780 ) <eddwo@[ ]pop.com ['hot' in gap]> on Thursday May 20, 2004 @05:53PM (#9209363)
    See Here [microsoft.com] for the white paper explaining the move to place GDI and USER in kernel space.

    The example they give is that the 3D pinball game runs great on Windows95 but terrible on NT 3.5 on the same hardware. Putting GDI in kernel mode was important to bring NT up to equivelent performance. Personally I think they found they couldn't get Win95s more complicated shell to run fast enough on NT, and they wanted to have the same environment on both Consumer and Business OS after all the Marketing that Windows 95 got.
  • by andy-at-vu ( 781800 ) on Friday May 21, 2004 @02:11PM (#9218261)
    After seeing all the responses yesterday, I think I have a better idea of Ken Brown's motivation in coming to see me and also his motivation in writing the book. If you are curious, take a look at

    www.cs.vu.nl/~ast/brown/followup

    Andy Tanenbaum
  • by Steve Hosgood ( 152793 ) on Monday May 24, 2004 @05:34AM (#9235905) Homepage
    As the original author of OMU, I can add a slight clarification. OMU09 (the 6809 version) was indeed single-tasking, but merely because the target system only had 64k of RAM, and it seemed pointless trying to multitask in such a small environment. It implemented an 'exec' call in much the style that MSDOS did, though I didn't know of MSDOS at the time.

    OMU68K was a port of OMU09 to the 68000 done mostly by Terry Barnaby. He ripped out the exec call and implemented fork() instead, so OMU68K did do multitasking.

    Of course, with no MMU on the 68000, it relied on well-behaved processes.

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