Analysts on OpenSolaris
By eschrock on Sep 21, 2004
There's been a lot of press about Sun recently thanks to our Network Computing 04Q3 event. It's hard to miss some of the coverage out there. Jim pointed out this article over at eWeek, which has some good suggestions, but also some gross misconceptions. I thought I'd look at some of the quotes and respond, as a Solaris kernel developer, and explain what OpenSolaris really means and why we're doing it.
First, there is the obligatory comment about Linux vs. Solaris within Sun. John Loiacono explained some of the reasons why we're investing in Solaris rather than jumping on the Linux bandwagon. To which Eric Raymond responded:
The claim that not controlling Linux limits one's ability to innovate is a load of horse puckey ... In open source, you always have that ability, up to and including forking the code base, if you don't like the way things are being run.
Taken out of context, this seems like an entirely reasonable position. But when you put it in the context of OpenSolaris vs. Linux, it quickly becomes irrelevant. The main reason we can't just jump into Linux is because Linux doesn't align with our engineering principles, and no amount of patches will ever change that. In the Solaris kernel group, we have strong beliefs in reliability, observability, serviceability, resource management, and binary compatibility. Linus has shown time and time again that these just aren't part of his core principles, and in the end he is in sole control of Linux's future. Projects such as crash dumps, kernel debuggers, and tracing frameworks have been repeatedly rejected by Linus, often because they are perceived as vendor added features. Not to mention the complete lack of commitment to binary compatibility (outside of the system call interface). Kernel developers make it nearly impossible to maintain a driver outside the Linux source tree (nVidia being the rare exception), whereas the same apps (and drivers) that you wrote for Solaris 2.5.1 will continue to run on Solaris 10. Large projects like Zones, DTrace, and Predictive Self Healing could never be integrated into Linux simply because they are too large and touch too many parts of the code. Kernel maintainers have rejected patches simply because of the amount of change (SMF, for example, modified over 1,000 files). That's not to say that Linux doesn't have many commendable principles, not the least of which is their commitment to open source. But there's just no way that we can shoehorn Solaris principles into the Linux kernel.
Of course, as Eric Raymond says, we could create a fork of the Linux kernel. But this idea lies somewhere between idealistic and completely ludicrous. First of all, there's the sheer engineering effort. Even after porting all the huge Solaris 10 (and 9, and 8 ...) features to a branch of the Linux kernel, we would enter into a perpetual game of "catchup" with the main branch. We'd be spending all of our time merging patches and testing rather than innovating. With features such as guaranteed binary compatibility, it may not even be possible. Forget the fact that such a fork would probably never be accepted by the Linux community at large. The real problem with creating a fork of the Linux kernel is simply that the GPL doesn't align with our corporate principles. We want to have ISVs embedding Solaris in their set-top box without worrying about how to dance around the GPL while keeping their IP private. Even if you can tiptoe around the issue now by putting your code in a self-contained module, the Linux kernel developers could actively work against you in the future. Of course, we could still choose a GPL compatible license for OpenSolaris, at which point I'll end up eating my words.
In the end, dumping Solaris into Linux makes no sense, either technically or philosophically. I have yet to hear a convincing argument of why ditching Solaris would be a good thing for Sun. And I can't begin to imagine justification for forking the Linux kernel. To be clear, we're not out to rule OpenSolaris with an iron fist. Because we own our intellectual property, we can make a licensing decision that reflects our corporate goals. And because we've put all the engineering effort behind that IP, we can instill similar beliefs into the community that we spawn. These beliefs may change over time: we would love to see a OpenSolaris community where we are merely a participant in a much larger game. But we'll be able to build a foundation with ideas that are important to us, and fundamentally different from those of the Linux community.
It's hard to know where to begin with statements like these. First and foremost is the idea that we will release Solaris "only for SPARC". No matter how many times we say it, people just don't seem to get it. Both x86 and SPARC are built from the same source! There is a very small bit of Solaris that is platform specific, and is scattered throughout the codebase such that it would be impossible to separate. Second, we've already stated that the license will be OSI compliant. I can't elaborate on specifics, and whether it will be GPL compatible, but it really shouldn't matter as long as it has OSI approval. The GPL is not the be-all, end-all of open source licenses. There are bad aspects of the GPL, and not every project in the world should use it. If we do end up being GPL-incompatible, the only downside will be that you cannot use the source code in Linux or another GPL project. But why must everything exist to contribute to Linux? I can't take Linux code and drop it into FreeBSD, so why can't the same be true with OpenSolaris? Not to mention the many benefits of being GPL-incompatible, like being able to mix OpenSolaris code with proprietary source code.
Most importantly, contributors to OpenSolaris won't just be helping "Sun improve its software." By nature of making it open source, it will no longer be "our software". All the good things that come with an OSI license (right to use, fork, and modify code) will prevent us from ever owning OpenSolaris. If you contribute, you will helping improve your software, which you can then use, modify, or repackage to your heart's content. You will be part of a community. Yes, it won't be the Linux community. But it will be a community you can choose to join, either as a developer or a user, as alternative to Linux.
Sun is hoping that making source code available will cause a community as large, as diverse and as enthusiastic as that around Linux to gather around Solaris. Just offering source code is not enough to create such a community. Sun would need to do a great deal of work to make that happen.
Now here's a comment (by Dan Kusnetzky of IDC) that actually makes sense. He understands that we are out to create a community. Like us, he knows that just throwing source code over the wall is not enough. He has good suggestions.
And we're listening. We have been researching this project for a very long time. We have talked to numerous customers, ISVs, and open source leaders to try and define what makes a community successful. Clever people have already noticed that we have begun a (invite only) pilot program; several open source advocates are already involved in helping us shape a vision for OpenSolaris. Creating a community doesn't happen overnight. We are gradually building something meaningful, being sure to take the right approach at each step. The community will evolve over time. And I'm looking forward to it.