The barbate characteristics of Richard Stallman, Alan Cox, John "Maddog" Hall and other forefathers of Linux and open source have long been iconic for hackers the world over. But as time grays the beards of these open source luminaries, the question becomes, "Who will replace them?" Just this question was posed by LWN editor Jonathan Corbet on April 14 during his roundtable talk at the Collaboration Summit of the Linux Foundation -- and opened a hornet's nest in the process.

Greg Kroah-Hartman, who works on the kernel for Novell, agrees that the old guard is still very much present, but needs to be because of the high change rate in the kernel. He added, "If we're in the way, let us know." Other developers concurred, that the code is complicated, but the oversight necessary. Only Andrew Morton showed signs of fatigue: "Yes, we're getting older, and we're getting more tired. I don't see people jumping with enthusiasm to work on things the way that I used to."

InformationWeek responded with a fitting title for its article on the Collaboration Summit: "Linux Graybeards? Yes, But Also a Wisdom Circle."

Is open source boring?

The jfplayhouse.com website went a step further by claiming that it wasn't a surprise that younger developers don't want to participate in the kernel. After all, they asserted, "Linux is one of the most boring open source software projects in existence. It's a massive heap of code that is mostly worked on by corporate developers." Add to that, that most kernel work is closed and there isn't very much interesting work to do on it: "Where is the appeal in spending your free time on a webcam driver when the completion of that driver will have zero bearing on the success of Linux?"

Comments to both articles included those from Jon Corbet himself, who opened up the subject in his Collaboration Summit talk in the first place. In Corbet's view kernel development is by no means dying off. On the contrary, he says, of the thousand or so developers involved in each three-month kernel release cycle, "nearly 20% of these contributors are working on their own time, because they want to." Among them are many first-time contributors. Corbet claims that the kernel is as attractive as ever, that there is more and more code to absorb into it. The issue, he says, is not the kernel itself, but the "graying of the ranks." Not that it is a problem. He continues, "James Bottomley suggested they may stay in place until they start dying off."

Graybeards as icons of wisdom

Sam Ramji, one-time open source representative at Microsoft, hosted an interesting panel at the 4th Collaboration Summit. Under the title "Does Open Source Mean Open Cloud?" Ramji called attention to his estimation that about 90% of all virtual machines run Linux, but that the SaaS structure supporting them is largely proprietary.

Therefore, the kernel and Linux community can continue to make use of graybeard services. This was also corroborated by Dan Frye of IBM in his keynote "10+ Years of Linux at IBM." When the company announced a decade ago that they would invest a billion dollars in Linux, it didn't fully understand the development model and tried in vain to bring code into the kernel. As it turned out later, both sides made some mistakes. Matt Mackall of the Mercurial project can remember how large blocks of code for hard disk volume management were rejected: "Linus didn't know what volume management was. For a long time it appeared to be going in, then it was rejected as 'just not salvageable'."

Meanwhile problems such as this have been dealt with more effectively and IBM has learned over the years how to best collaborate on kernel development. Google has also picked up some similar experience. After developing Android for quite a while behind closed doors and not coordinating with the kernel, new parts of Android are now finding their way back in. Kernel developers will now probably be confronted by huge new blocks of code. To prepare for the eventuality and contribute a positive atmosphere, Google handed out a Nexus One to each of the Collaboration Summit participants.