Re: Xen is a feature

George Dunlap
2009-06-04T13:21:20Z

Frans Pop wrote:
> ! The kernel policy always was and still is to accept only those
> ! features which have a technical benefit **to the code base**.
>
Yes, I think I understood him better after I responded to his e-mail
(unfortunately). When people say things like "dom0 adds all these hooks
but doesn't add anything to Linux", they mean something like this
(please correct me anyone, if I'm wrong).

Kernel developers want Linux, as a project, to have cool things in it.
They want it to be cool. Adding new features, new capabilities, new
technical code, makes it cooler. Sometimes adding new features to make
it cooler has some cost in terms of adding things to other parts of the
code, possibly making it a little less clean or a little more
convoluted. But if the coolness is cool enough, it's worth the cost.

The feeling is that adding a bunch of these dom0 hooks (especially of
the type, "if(xen) { foo; }"), are a cost to Linux. They make the code
ugly. They do allow a new kind of coolness, a (linux-dom0 + Xen)
coolness. But none of the coolness actually happens in Linux; it all
happens in Xen. So coolness may happen, and world happiness might
increase marginally, but Linux itself doesn't seem any cooler, it just
has the cost of all these ugly hooks. Thus the "Linux is Xen's sex
slave" analogy. :-)

If (hypothetically) we merged Xen into Linux, then (people are
suggesting) the coolness of Xen would actually contribute to the
coolness of Linux ("add technical benefit to the code base"). People
would feel like working on the interface between linux-xen and the rest
of linux would be making their own piece of software, Linux, work
better, rather than feeling like they have to work with some foreign
project that doesn't make their code any cooler.

Is that a pretty accurate representation of the "adding features which
have a technical benefit to the code base" argument?

-George