Linux kernel team grows, Torvalds drops off chart

The 2009 report on the state of Linux kernel development (pdf) has been published by the Linux Foundation. Although all the information in it is drawn from the development management process and is thus already public, it brings together some statistics that shows how Linux is growing and who's contributing.

Over the past 16 months, the report says, 2.7 million lines have been added, there's been a ten percent increase in the number of developers contributing to each three-monthly release cycle, and the number of lines of code contributed each day has nearly tripled. Some five thousand developers across more than five hundred companies are involved: of those companies, Red Hat is in the lead with 12 percent of changes, IBM on 6.3 percent, Novel on 6.1 and Intel on 6.

Developers also sign off code when it's ready to be included in the kernel; here, Red Hat accounts for 36.4 percent and Google - which contributes under one percent of code - is second, signing off 10.5 percent of changes.

The report notes the long tail of companies who don't appear in the top lists but still actively contribute, often in specialist areas. Sony, Nokia and Samsung are all mentioned as adding code that supports consumer electronic equipment, with other code coming from Volkswagen for automobile networking and Quantum Controls BV, which makes navigational devices for yachts. With this breadth and depth of support, the report concludes, "even if the largest contributor were to cease participation tomorrow, the Linux kernel would remain on a solid footing with a large and active development community." It also says that the process of submitting code for inclusion in the kernel encourages a methodical, component-based approach to writing software which promotes reliability and maintainability.

In a footnote, the report says that Linus Torvalds himself, creator of the Linux project, has fallen off the Top 30 contributors' list since the previous report in 2008, mostly for reasons connected with the sort of work he does on the kernel. He's still an "active and crucial" part of the process, the report reassures.