A small note on the Linux SCM saga

Newsforge is running an interview with the three main participants in The Great Linux SCM Saga, Linux, Larry McVoy, and Tridge. By and large, it’s a good article, but I suspect that someone who didn’t know the people involved would assume that the whole mess was Tridge’s fault–he’s the one that was working on cloning BitKeeper, even though any sane person would know that it would really piss Larry off. Even after people pointed this fact out to him, he kept working on his BitKeeper tools.

I’d be remiss if I didn’t point out that Tridge has a history of doing this sort of thing. I’m aware of two other cases where he’s dug in and reverse-engineered similar sets of protocols and file formats. The first time, the result was Samba, which was (and still is) really one of Linux’s first killer apps. The second time, he decoded TiVo’s on-disk media format. Pretty much any tool on the net that knows how to extract video from TiVos (except for TiVo’s recent TiVo-to-Go release) is based on Tridge’s work.

That’s not to say that reverse-engineering is all that he does–rsync is his too.

I remember people questioning his ethics during his TiVo work–besides just downloading video from TiVos, his would could (in theory at least) allow someone to buy a TiVo and feed it program guide information without paying TiVo’s monthly subscription. Without that, TiVo’s revenue model falls apart, and the company would be forced to either sue their own users or go out of business. The BitKeeper folks might have paid attention to how he handled the TiVo issue–as I recall, he released the video download code, but kept the programming guide code to himself. In some ways, that actually helped TiVo–I had no qualms about buying a second TiVo, even when their financial footing was shaky. Without Tridge’s programming guide code, a TiVo box without TiVo, Inc would just be a big paperweight. Just knowing that the program guide code existed was enough to ensure that my TiVo would continue to be useful, because someone would pick up the torch if TiVo fell.

I don’t know what Tridge was planning to do with his BitKeeper tool, but based on his past record, I really doubt that he would have used it to sabotage BitMover. Or, at least not to do anything that he saw as sabotage. Clearly Larry McVoy (and to some extent Linus) saw things differently.

Getting off of BitKeeper is probably best for Linux in the long run. It’s a pity we couldn’t have waited for another year or so for open-source SCM software to mature more, though. There are a number of promising contenders, but they all have issues that keep them from being usable for the Linux kernel today.

Posted by Scott Laird Mon, 11 Apr 2005 18:12:25 GMT