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The Linus Torvalds Bus Factor

About this Document

This is an email exchange, that was converted into a web page. While originally intended to start a discussion on the Linux kernel mailing list it is in fact more general, and illustrates a good point about open source software development.

Table of Contents

Document Information

Written By:
Shlomi Fish
Finish Date:
TODO : 5-April-2007
Last Updated:
TODO : 8-April-2007

Licence

Creative Commons License

This document is Copyright by Shlomi Fish, 2006, and is available under the terms of the Creative Commons Attribution License 3.0 Unported (or at your option any later version of that licence).

For securing additional rights, please contact Shlomi Fish and see the explicit requirements that are being spelt from abiding by that licence.

The Article Itself

First Email

The purpose of this email is two-fold:

  1. To make sure that Linus Torvalds hits himself with a bus. I.e.: resigns from his role as the benevolent dictator of the Linux kernel, at least temporarily.
  2. To advocate the enactment of a central git repository with several commiters.

I’ll start with No. 2.

From what I understood, at the moment, only Linus can commit or accept pulled changes to the repository of the vanilla tree. Other people have their own personal repositories as well. This system works, but I believe it is sub-optimal. Here are some examples why:

  1. Subversion. 126 people with a commit bit - some of them inactive, but still. I recall being present at #svn or #svn-dev on Freenode and seeing the commits come by from the CIA bot constantly. (Some people apparently never sleep.)

  2. Pugs. Audrey Tang is extremely liberal about giving people commit access. She gives it to practically everyone who asks or who has something to contribute just so she or whoever, won’t be bothered with committing it themselves. Even I received a commit despite my notorious perl6-critique essay. Larry Wall has said that it makes Pugs “a happy hivemind. Er, I mean family”.

    And Pugs still works pretty well, even if it is slow.

  3. KDE. KDE takes this to extreme. 100s of people with commit access - perhaps even 1,000s. Commits are handed out liberally. And yet KDE works very well, has many features, and is mostly bug free. It is so good that even the Linus uses it, and has advocated.

    Just for completeness sake, I should note that it also exists to some extent with GNOME, but I cannot testify how liberally the commits there are given. I have a commit bit there, too, but it took me some more time than with KDE, where I received it as a birthday present for my 24+57/365’s birthday.

---------------

None of these projects are using git - they are using Subversion now, and some of them were using CVS to a great degree of the same effectiveness beforehand. And they are all doing very well, and the integrity of the code is preserved.

Now, if we have the same for the Linux kernel (and I believe git has no problem allowing it), then it will simplify processses, facilitate commiting some simple changes, and generally make everyone happier. If Al Viro (for example) can commit directly to the central repository a patch that re-indents some code, it will be a better idea than to have him commit it to his own and then request Linus to pull it from there.

Note that having many commiters does not mean anarchy. When I got a commit bit to the central Subversion repository, I still submitted most patches for peer review, because I was not confident enough to apply them myself. The same happened with the GIMP, where I received a full allowance to do whatever I pleased with the gimpressionist plug-in, but still was not confident in commiting my patches directly to the GIMP core without consulting anyone. So I sent them to peer review on the GIMP bug tracker, and after everyone were happy with them (which ususally involved several iterations), I was able to commit them.

What the KDE people do is that they ensure the quality of the SVN snapshots by monitoring the commits feed, and by testing them extensively. And it works: KDE is relatively bug free, and works pretty well, despite the fact that everyone and his sister-in-law has a commit bit.

Note that you don’t have to depend on Linus or whoever to do this. You can simply take the initiative and give commits to your own repository to people who trust. You can call it a subversive (pardon the pun with svn) movement. Linus may disapprove but since Linux is open source, you don’t need to ask him. If Linus wishes he can eventually pull the relevant changes from the multi-commit repository.

Which brings us to issue No. 1:

Ben Collins-Sussman and Brian Fitzpatrick talk in their Google Video presentation “How Open Source Project Survive Poisonous People (And You Can Too)” about the “bus factor”: how many developers need to be hit by a bus so a project would be neutralised. This number is probably very high for the Linux kernel, as many people know its internals in and out.

However, I’m worried about something slightly different. I’m worried about the fact that Linus Torvalds started the Linux kernel project, and is still heading it after 14 years, where it evolved from being a toy, to an “enterprise-grade, industrial strength” kernel that is used anywhere from 8 MB embedded devices to super-computers, not to mention being the second or third most popular desktop system (and second on IBM PCs) and the second or first most popular for servers.

I’m not saying Linus is not doing a good job - almost everyone agrees that he has been doing an exceptional job. However, being the benevolent dictator ( “for life” ) has made him the bottleneck, the poster boy, the scape goat, the ultimate authority, and lots of other roles that he defaults to play. This is unhealthy for the project.

It is known that Solon said he was leaving Athens for a trip around the world, in the midst of his reform for several years. But he in fact moved to a nearby Island where he observed by proxy how they managed without him. Without being an insider of the Linux kernel mailing list, I believe Linus voluntarily leaving will have a positive effect.

At the moment everyone defaults to Linus, but if he “hit himself with a bus”, they’ll have to manage without him. This will eventually lead to a better internal organisation, and a much more robust solution. There might be a different benevolent dictator. There might be a central git repository with many committers. There might be something else. But it will be better than it is today.

I hate the term “benevolent dictator for life”, because it assumes the person cannot be overthrown or that there cannot be a mutiny (my term for coup) against him. A benevolent dictator in the free software world must not be for life because he may not be the best solution for ever.

Now that I think of it, I find it sad that people think of the Linux kernel project as “Linus Torvalds’ baby”. Compare it to KDE which is a large amorphous meta-project, with no-one known in particular, to Subversion, which while having many prominent contributors has no poster child. And then there’s Perl, which while Larry Wall is its undoubted demi-god, has many other prominent figures.

Of course, like I said, you can do a mutiny without asking Linus, by starting out a central repository for the kernel with many commiters. If this works, then this repository may eventually become the de-facto kernel (and Linus would no longer be the benevolent dictator). If it won’t work, then we’re not better off, but very little time was wasted.

Linus *can* resign willingly, which may be even more desirable. However, the Linux kernel is a FOSS project after all, and if you don’t like something, you can always fork it, or at least create your own branch, patchset, etc. in the version control repository.

Let the flames begin!

David Miller’s Response

David Miller made a short response to the thread:

Please nobody reply to his posting, I’m shit-canning this thread from the start as it’s nothing but flame fodder.

My Response to David Miller

I sent the following response to David Miller after a while. It never arrived at LKML for some reason.

Hi Mr. Miller!

Must resist urge.... people are human... they perform logical fallacies...

Oh! What the heck!

Please nobody reply to his posting.

Fair enough.

I’m shit-canning this thread from the start as it’s nothing but flame fodder.

“Nothing but flame fodder”. How many logical fallacies are in these 4 words:

  1. Labeling. You’ve labeled my message as “flame fodder” so “it Must be the Truth”. But any assertion requires a burden of proof:

    Show me the Reasoning!!!

    ( Who’s your m*****-f****ing Jewboy brother, David? )

  2. Lack of proof - see above.

  3. All or nothing thinking and over-generalisation. You’ve said it’s “nothing but flame fodder”, so you’ve told us that assuming it is indeed flame fodder (which may be the case) than it is *nothing but* that.

  4. Evasion - you’ve not replied to any of my suggestions or reasoning. Instead, you just implied “You suck”.

Now I’m not saying what I said is indeed a good idea. It may or may not be. But this is not the mature and philosophically valid way to deal with it.

I purposely said “Let the flames begin” at the end to be whimsical and to let people think twice before they do it. I could consider what you wrote as a flame as well. (Although possibly a “fight fire with fire” one).

For your information what I suggested has been brewing up for a long time.

I wrote this message in the course of about two hours, and then consulted people on the IRC on it. I cited several URLs and references. I have made a lot of contribution to free software in the past, but even if I did not, I believe my suggestion should have been dealt with by explaining to me why what I suggested was a bad idea, in your opinion.

Best regards,

-- Shlomi Fish (who happens to have a natural obsession with Applied Logic. It’s a curse, but often is also a blessing)

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