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I just wanted to point out that the "Computer Science professor" mentioned in the /. blurb is "The" Andrew S. Tannenbaum, inventor of minix, and author of several textbooks used in Computer Science programs nationwide.

Personally, I would not have posted that article without attaching these links. Tannenbaum is a key player in modern computer science research and education.

Check out his homepage
and his Wiki biography.

The University is called the "Vrije Universiteit" or VU for short ( http://www.english.vu.nl/home/index.cfm/ ). Which is not "Free as in Beer". It also didn't stand for Free as in: open for everyone. That didn't come along until the 1960's.

Performance problems are a well-known fundamental problem with microkernel architectures that use user-mode processes.

It's a widely-believed myth, mainly due to the poor performance of bloated first-generation microkernels like Mach, although I suppose it probably also applies to Linux when Linux acts as a microkernel.

Google is your friend.

Just because Linus Torvalds thought something was impossible during the 1990s doesn't make it so, so I suggest you skip the infamous Linus vs. AST discussion from that time period.

The reality is that:

1. Microkernel architectures are hard to design. This is suspected as being the real reason why they are not very popular today.
2. Monolithic kernel architectures are prone to insecurities. There is just way too much privileged code, and too many failure scenarios.

Unlike Linus, some people are actually devoting much of their time to solving these problems. AST is one such person. See this page on the subject.

But wait, the BitTorrent tracker they're using is hosting a copyrighted DVD-R of the movie "The Man Who Knew Too Much (1934)."

Tracker webpage: http://jip.cs.vu.nl:6969/

Irony at its best! :)

Do we really need to quote the whole article directly just to get you to read it?

There were endless comments on Slashdot Monday (May 8) of the form: "If microkernels are so good, why aren't there any?" Actually there are. Besides MINIX 3, there are:

• QNX
• Integrity
• PikeOS
• Symbian
• L4Linux
• Singularity
• K42
• Mac OS X
• HURD
• Coyotos

QNX is widely used in real commercial systems. Cisco's top-of-the-line router uses it, for example, and I can assure you, Cisco cares a **LOT** about performance.

One of the leading operating systems in the military and aerospace markets, where reliability is absolutely critical is Green Hills' Integrity, another microkernel.

PikeOS is another microkernel-based real-time system widely used in defense, aerospace, automotive, and industrial applications.

Symbian is yet another popular microkernel, primarily used in cell phones. It is not a pure microkernel, however, but something of a hybrid, with drivers in the kernel, but the file system, networking, and telephony in user space.

Really, is reading the article that hard?

you mean like Tanenbaum (slashdotted, try later) did?

FTFA:

So **PLEASE** no more comments like "If Tanenbaum thinks microkernels are so great, why doesn't he write an OS based on one?" He did.

i don't reall know what you mean by proof of concept

again, FTFA:

It is definitely not as complete or mature as Linux or BSD yet, but it clearly demonstrates that implementing a reliable, self-healing, multiserver UNIX clone in user space based on a small, easy-to-understand microkernel is doable. Don't confuse lack of maturity (we've only been at it for a bit over a year with three people) with issues relating to microkernels.

i know this is slashdot, and RTFA is some kind of mortal sin, but please at least try.

1. From AST (I'd assume you know who he is since you are interested in Linus/microkernel debate): http://www.cs.vu.nl/~ast/brown/followup/ Read the section "Microkernels Revisited":

I can't resist saying a few words about microkernels. A microkernel is a very small kernel. If the file system runs inside the kernel, it is NOT a microkernel. The microkernel should handle low-level process management, scheduling, interprocess communication, interrupt handling, and the basics of memory management and little else. ... Microsoft claimed that Windows NT 3.51 was a microkernel. It wasn't. It wasn't even close. Even they dropped the claim with NT 4.0.

2. From Windows Internals, the 4th edition, published by Microsoft Press. Page 36: Windows is similar to most Unix systems in that it's a monolithic operating system in the sense that the bulk of the operating system and device driver code shares the same kernel-mode protected memory space. Can we stop claiming Windows has a microkernel now?

Climatology has been so thoroughly politicised that scientists and activists are not easily distinguished.

The reason is that fear and hysteria generate press, political pressure, and therefore funding urgency. Also green activists readily identify with the subject matter and hysteria, much moreso than with more esoteric fields.

Now there is a runaway feedback cycle!

Remember that Minix Master and Amoeba Artiste AST spells his name with two, not three, Ns: Andrew Tanenbaum.
I learned so much dissecting Minix version 1 way back when, I have a warm place in my heart for that guy.

I did a double-take when I saw Andrew Tannenbaum on the list of legal representatives. Closer inspection showed that he is a Trial Attorney for the US DOJ -- not the same (very) geek-famous Andrew Tannenbaum. I need some of CowboyNeal's coffee. :)

For those interested in the actual paper (Phys. Rev. Lett. 96), the PDF is available on the researcher's publications page:

http://www.nat.vu.nl/~wimu/PUBS.html

I agree with you overall, but I do take issue with this point. In the beginning it wasn't certain that there would be a clearly defined court case. Most Linux supporters felt that since development was done in the open it would be difficult if not impossible to get improper code accepted into the Linux kernel. However, there were those who felt that since there wasn't a central authority vetting the code it would be easy for someone to misappropriate code and have it accepted.

Another interesting connection is that intellectual property issues are frequently presented as a reason to go with Windows on Microsoft's Get the Facts website. For example, Radio Shack's case study mentions reducing "exposure to the risk of intellectual property infringement claims" as a reason to go with Windows over Linux. Before SCO starting suing their customers for using Linux, who was worried about a lawsuit over their choice of operating system?

I think Microsoft is responsible to some degree for SCO's suit. I think someone didn't fully understand the way Linux development happens and badly miscalculated the effect of the lawsuit on IBM. If IBM had quickly settled then there would be plenty of room for "no smoke without fire" FUD about the risk of improper code in Linux. Because the suit has gone on for so long and there have been so many people with enough stake in vindicating Linux there have been multiple opportunities for demonstrating that there is no infringing code.

I agree with you overall, but I do take issue with this point. In the beginning it wasn't certain that there would be a clearly defined court case. Most Linux supporters felt that since development was done in the open it would be difficult if not impossible to get improper code accepted into the Linux kernel. However, there were those who felt that since there wasn't a central authority vetting the code it would be easy for someone to misappropriate code and have it accepted.

Another interesting connection is that intellectual property issues are frequently presented as a reason to go with Windows on Microsoft's Get the Facts website. For example, Radio Shack's case study mentions reducing "exposure to the risk of intellectual property infringement claims" as a reason to go with Windows over Linux. Before SCO starting suing their customers for using Linux, who was worried about a lawsuit over their choice of operating system?

I think Microsoft is responsible to some degree for SCO's suit. I think someone didn't fully understand the way Linux development happens and badly miscalculated the effect of the lawsuit on IBM. If IBM had quickly settled then there would be plenty of room for "no smoke without fire" FUD about the risk of improper code in Linux. Because the suit has gone on for so long and there have been so many people with enough stake in vindicating Linux there have been multiple opportunities for demonstrating that there is no infringing code.

It definitely isn't, trust me. I'm a ...biologist.

I mean the picture, of course: http://images.slashdot.org/topics/topicworms.gif -- it is an insect larva, not a worm. To be more specific -- probably a butterfly caterpillar.

You want to see a worm? Here -> http://www.desc.med.vu.nl/NL-taxi/ICE/C_elegans1.j pg is a nice picture of C.elegans, The Model Worm (r).

January

He said he's in the consulting industry. That make me wonder what kind of idiots would hire him as an IT consultant?

Minix comes to mind as it was and is designed to work on old machines (at least a 386 with 8MB of ram). It's not as "mature" as the other *nixes of course but you can turn trash into servers with it.

True, but you overlooked the fact that I said, "I meant switch over from GNU/Linux!" [emphasis added]. You think you're contradicting me, but you're not.

Linus Torvalds -- then a student of Tanenbaum

Torvalds was never a student of Tanenbaum. Like many computing students the world over, myself included, he learned something about OS hacking using Minix, which is Tanenbaum's baby, but he wasn't a student of Tanenbaum. Tanenbaum teaches at Vrije Universiteit in the Netherlands; Torvalds went to Helsinki University in Finland.

Linux really was first created just to prove a point: that a monolithic kernel could sometimes outperform a microkernel

No, that's not right either. Presumably this fiction follows from your earlier fiction about Linus being a student of Tanenbaum. Tanenbaum's take on the matter is as follows.

Before there was Linux there was MINIX, which had a 40,000-person newsgroup, most of whom were sending me email every day. I was going crazy with the endless stream of new features people were sending me. I kept refusing them all because I wanted to keep MINIX small enough for my students to understand in one semester. My consistent refusal to add all these new features is what inspired Linus to write Linux. Both of us are now happy with the results. [Source: Tanenbaum's FAQ]

Go brush up on your research skills. We can work on your stylistic elements after you get your facts straight.

His bio so in terms of why he gets to grade Linux as an F (IMO he was right, its improved since but it was poor, SMP, size of kernel, modularity, the only advantage was that NT and Windows scored a "Not Classified") its because he managed to understand Operating system design to such a level that his work was the BASIS from which Linus was "inspired".

Minix and his work are key reference works in writing pretty much any OS and his work in computer networking and distribution in paticular are top notch. His stuff is very much NOT Ivory Tower (I speak as someone who has had to do bespoke OS work) and very practical way to build operating systems and overcome networking challenges. Heard of the OSI model for networking? Most of the rest of us have heard of it thanks to Andy's work, because we couldn't afford the official reference from ANSI/ISO.

Out of interest what is you have done?

Why, yes, yes it does.

Don't forget to check out the Steganography demo (link at bottom of page)

Tannenbaum's home page:

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

Yes, it's the same guy who wrote the book for your networking course.

It looks like you can download an evaluation version of VMWare workstation that "dies" in one month. I'm not sure if you can create a VM with that, then play it with player, or if they're DRMed, but it's at VMWare's site.

You could also download a virtual machine here it looks like. I'm sure if you google you can find others.

Andrew Tanenbaum's cook book: "How To Prepare Your Input" (available here in PDF!)

Linus started out using Minux, and alot of the early linux guys came from the minux mailing list. Linus used minux as a development platform to write, and compile linux. Don't take my word for take Andrew's word for it. http://www.cs.vu.nl/~ast/brown/rebuttal/

Early on in the case, this would have been a huge big revelation...

Yeah, that's why I wrote this post, you probably didn't see it since it was just a minute before yours :)

Anyway, I don't understand why they'll need for a simulation like this. Will the virtual beings build a whole universe? Simulations aren't usually so slow. I found this page which probably has more interesting information, maybe I'll check it out later :)

There is also a request in GNOME bugzilla to implement this in GTK+.

You are correct that it is a Posix compliant OS. It is also a copy of Minix which is a copy of Unix ("MINIX is a free UNIX clone..." Andrew S. Tanenbaum http://www.cs.vu.nl/~ast/minix.html)

So, the point is still that Linux was not "invented" by anyone in Europe, it was copied from the work of a European that was copied from the work of Americans.

A friend of mine implemented tetris using a laser to trap 1 mirometre glass beads. Short story + picture + video here. More explanation here.

A friend of mine implemented tetris using a laser to trap 1 mirometre glass beads. Short story + picture + video here. More explanation here.

Just FYI, the other guy is Andrew Tannenbaum, who wrote Minix

As for winning or losing, you can see for yourself on Google Groups that it was not about winning, it was a discussion on the merits of both.

Your parent poster is right. Linux is a Unix clone, as per the general meaning of that word in computing.

> Unless you mean something different by "clone" than the rest of the world.
Most people are comfortable using the word "clone" to describe 'work alikes', and not just systems that share source code.

- You can see this if you google for "Linus Unix clone".

- Andrew Tanenbaum calls Minix "a minimal UNIX clone", (though he didn't use any AT&T UNIX source)

- Linus' initial usenet posting called Linux "a minix-lookalike". At the time, Linux was quite depedant on Minix, needing Minix sources to compile (though no Minix source was used in Linux).

- Linux was also a Minix (and hence a Unix) 'work alike'. In the same post, Linus expressed interest in reusing existing code written for Minix, for Linux: I'm also interested in hearing from anybody who has written any of the utilities/library functions for minix. If your efforts are freely
distributable (under copyright or even public domain), I'd like to hear from you, so I can add them to the system.

- The parent post qualified his statement, saying DOS was "a clone of CPM/86, in EXACTLY the same way Linus Torvalds created a clone of Minix/Unix."

I'm going to go out on a limb here and hazard a guess that if I said, 'NetBSD,'

Minix was a teaching tool to teach OS design concepts - with source.

However, it looks like redistribution of Minix is permitted as long as you keep the Minix license in the file. So if you're allowed to use the code elsewhere -- so Linus could legally use as much of the code as he wanted, and didn't need to rewrite any of it later if he didn't want to.

The only way I'd see that using this code wasn't OK would be if it wasn't OK for Andy Tanenbaum and Kees J. Bot and any other authors of Minix to give away, because it wasn't their code. Which seems odd, but it does sound like about par for the SCO course :)

Minix was a teaching tool to teach OS design concepts - with source.

However, it looks like redistribution of Minix is permitted as long as you keep the Minix license in the file. So if you're allowed to use the code elsewhere -- so Linus could legally use as much of the code as he wanted, and didn't need to rewrite any of it later if he didn't want to.

The only way I'd see that using this code wasn't OK would be if it wasn't OK for Andy Tanenbaum and Kees J. Bot and any other authors of Minix to give away, because it wasn't their code. Which seems odd, but it does sound like about par for the SCO course :)

see AST's home page

The author ignores a number of inconvenient facts.

First, and foremost, SCO's bluster about Linux and copyright infringement predates their lawsuit against IBM. Whether or not IBM violated its contract with SCO is not the community's beef with SCO; the community is up in arms because SCO had the gall to suggest that Linux was a big ripoff of SCO's proprietary unix code and began to do things like sell linux licenses, as if it had some right to collect that money. So this is not merely a "simple contract dispute".

Moreover, he is skewing the origin of Linux. Regardless of the author's qualifications, the two people most able to state whether or not Linux was or was not dervied from Minix or contained Minix code would certainly be Linus Torvalds and Andrew Tannenbaum. Tannenbaum said, "I told [Ken Brown, President of the Alexis de Tocqueville Institution] that MINIX had clearly had a huge influence on Linux in many ways, from the layout of the file system to the names in the source tree, but I didn't think Linus had used any of my code." Eric Raymond may have been citing this to make a point, but when Linus and Andrew both are clear on the point that Linux did not use Minix code, then I believe take their assertions on that point.

The assertions about due diligence are equally off-base, as the Open Source Risk Management company is offering insurance against claims of copyright infringement. It is basically absurd to suggest they could get millions and millions of dollars of insurance underwritten without due diligence against the product they were insuring - which, in this case, is the code that comprises Linux.

Finally, the author completely ignores how unclean SCO is with its own source management. They distributed a version of Linux for quite some time, and continued to distribute it even after they had made public claims. If they had discovered claims but continued to distribute the code, one could quite easily argue (and surely IBM will) that they have themselves have placed whatever code is in question under the GPL.

This only touches on the number of issues he manages to gloss over in a few brief pages. By no means do I think that David Boies would have been involved on contingency unless he felt he had some chance of winning, but the fact is, SCO is bleeding money like tomorrow's bacon, and it is hard to imagine how anyone would care to purchase a real product from SCO in the future, given their propensity to do things like, say, sue their customers.

Certainly, at this point, Canopy can only be hoping that the payoff from the lawsuit against IBM and other actions will be sufficient to justify flushing the company. But even *if* SCO managed to prove IBM contributed tainted code, there's a mountain of counterclaims to deal with and SCO has to try to establish damages, and it's hard to see how SCO can justify damages that are a significant multiple of its own market capitalization at the time the offense occurred. It would be like Harold Welte suing Asus for $2B or such. It may sound like a nice round number, and SCO can say that it wants "infinity times infinity" for damages, but that doesn't give it a snowball's chance in hell of actually seeing such damages.

And here I thought Minix was written by Andy Tanenbaum. (notice the NL in that domain?)

Dig a little deeper into that link you provided, and you'll find this FAQ about Andy Tanenbaum, which includes this info:

Your name is German, you live in The Netherlands, but you write almost as well as a native English speaker. What's the scoop?

My paternal grandfather was born in Chorostkow, currently in Ukraine, historically in Poland, at the time under Austro-Hungarian management. He came to the U.S. in 1914. I was born in New York and grew up in White Plains, NY. I went to Amsterdam as a postdoc and have sort of hung around ever since.

Where did you go to school?

High School: White Plains High School
College: M.I.T.
Ph.D.: University of California at Berkeley

So yeah, Minix was written by an American who happens to live in Amsterdam.

Nice job on the moderation there.

1. And here I thought Minix was written by Andy Tanenbaum. (notice the NL in that domain?)

Most of the stuff you are talking about is, with all due respect, old stuff. I'm not going to argue about whether or not Americans are stupid or not (it's a rediculous generalization), I think it's entirely possible that a new generation does not have the level of education than the one before. I think we can all agree that your ancestors where great. You will have to prove yourself.

2. Sure, Americans never lie on their resume. I'll give you that one.

3. How about you don't sit back and wait for Microsoft to do the right thing? It's easier than ever to create 'the next big thing' in your garage/basement. For example, you can get an FPGA development kit for under a $100, with which you can do just amazing things. Quit your fucking whining and start doing something.

4. Getting a little desperate to have a good argument, it sounds like.

5. Instead of silly personal attacks on people, how about this; why don't you dedicate some energy to see how you can help to get a government in place that is for the people and not the corporations. You realize that it is your government that is _very_ supportive of Microsoft, and that that government was (supposedly) democratically chosen.

Maybe Andy was right; Linux probably wouldn't require such a sophisticated, distributed RCS if it were not a monolithic kernel:^)

...and it is not a native programming language...

Actually there are native compilers available for Java: Gcj, J2exe,
Excelsior JET and Manta.

There are downsides to using native compilers though, including a) the need to maintain separate platform versions of your app, and b) the loss of the ability to decompile back to Java source. But some developers don't mind a), and the more proprietary ones positively love b). :)

Kaffe, on the other hand, isn't a native compiler in the sense that the compilers above actually cough up an executable for you at the command line. But it has a just-in-time (JIT) compilation system which translates the bytecode to native machine code on a method-by-method basis as the application is executed. This really boosts Java app performance a lot.

Actually, Java would be perfect for managing a grid.

If you think so, check it ibis. You can download the latest version from the link and play around with it. Or read this old slashdot story

disclaimer: I'm not directly involved with the project, but working in the same group as the developers. And I don't mind pushing a good idea :)

Also, with the issue of indemnification, who would be a potential litigant against linux when SCO's dead? Novell, who owns SuSE?

I've asked that exact question myself. The only person who could really do damage in this regard would be Andrew S. Tanenbaum, although that actually happening is far from likely.

My glorified 386 is faster than your RISC "workstation", and way cheaper.

Who told ya that I run a minix kernel? Even Tanenbaum, the Minix creator, acknowledges that Linux IS NOT A MINIX DERIVATIVE (seen at Tanenbaum's home page); even if it was, what is wrong with it? It runs great on many many kinds of hardware (including your beloved RISC "workstations").

Deal with it, while you are running a wanna-be RISC workstation, and a wanna-be UNIX kernel, the rest of us are going to get the fastest CISC workstations, with the latest and greatest from the best developers all around the world.

See:

Mac SE Server
Webserver Mac SE
Another Mac SE Server

( The SE is a 68000 Motorola running at 8mhz on 4MB of ram. So if you can *avoid* clicking the last link directly *today* I'm sure the owner would appricate it. )

As for short life cycles - oh please. I've was using a G4 single CPU then a G4 dual CPU for 3 yrs before the G5 came out. The G4 was a VERY long life cycle for a CPU.

As for getting parts, in my 20+ yrs with Apple hardware I have NEVER replaced anything other than hard drives which have ALWAYS been stock (and NOT made by Apple). OMG this is a pointless argument. Where do you misinformed twats come from anyway? It's a never ending story with you WinTel people is it?

Hi guys,

Our group actually has a paper in this years HPDC conference, that shows a method to do hole puncing with TCP. We call it TCP splicing. This way, you don't have to implement a reliability protocol on top of UDP.

You can find it at www.cs.vu.nl/ibis -> publications...

Alexandre Denis, Olivier Aumage, Rutger Hofman, Kees Verstoep, Thilo Kielmann, Henri E. Bal:
Wide-Area Communication for Grids: An Integrated Solution to Connectivity, Performance and Security Problems,
Accepted for publication, HPDC-13, June 2004, Honolulu, USA.

Here is a direct link:

http://www.cs.vu.nl/ibis/papers/hpdc2004-denis.pdf

Cheers,

Rob

"[F]or anyone to be surprised that an OS designed to be run for a single user in a non-networked environment loaded with legacy code to fully (and successfully) port to a multi-user, networked environment shows a lack of understanding about the increasing inertia software products have as they age."

Amen, brother!

I mean, when was the last time we heard of some dusty old professor writing a toy OS for the edification of his students, only to have some graduate student study it for a bit, then get together with a bunch of pals and create one of the best OSes in the world?

*blink*

Honestly, its easier to write a recursive descent parser by hand for a programming language than you think, and interpreters are ridiculously easy unless you're worried about making it fast, which is way overrated too. It mattered with 640KB of RAM at 20MHz, but these days, its just stupid to care unless you notice its insanely slow.

First off, if you've not found this link: http://compilers.iecc.com/crenshaw/, then I recommend you start with it. While its about writing a compiler, it really help make parsing much clearer.

Scheme is a good language to check out if you want to start with another design(a scheme interpreter can be written in a few hours, even in C, if you're slick, even if you're not, it would be short project to get 90%).

Some other reference material: Parsing Techniques(free online). Also: Modern Compiler Design by the same guys and well worth the investment. Concepts, Techniques, and Models of Programming Languages, teaches kernal theory of language design, and may open your mind to some other techniques you may not be aware of.

Checking out the archives on Lambda The Ultimate would be wise too. Also, if you're in Boston on December the 4th, you might check out the Lightweight Languages Workshop at MIT.

Honestly, its easier to write a recursive descent parser by hand for a programming language than you think, and interpreters are ridiculously easy unless you're worried about making it fast, which is way overrated too. It mattered with 640KB of RAM at 20MHz, but these days, its just stupid to care unless you notice its insanely slow.

First off, if you've not found this link: http://compilers.iecc.com/crenshaw/, then I recommend you start with it. While its about writing a compiler, it really help make parsing much clearer.

Scheme is a good language to check out if you want to start with another design(a scheme interpreter can be written in a few hours, even in C, if you're slick, even if you're not, it would be short project to get 90%).

Some other reference material: Parsing Techniques(free online). Also: Modern Compiler Design by the same guys and well worth the investment. Concepts, Techniques, and Models of Programming Languages, teaches kernal theory of language design, and may open your mind to some other techniques you may not be aware of.

Checking out the archives on Lambda The Ultimate would be wise too. Also, if you're in Boston on December the 4th, you might check out the Lightweight Languages Workshop at MIT.

Yeah, he means MINIX, the microkernel based O.S. developed by Andrew S. Tanenbaum. As far as I can tell, Minux is a small Linux distribution developed by Roland Wehren.

Tanenbaum is the owner of electoral-vote.com.