Custom kernel building

[Paul Bolle]

On Sun, 2011-04-17 at 22:20 +0000, Guilherme Patriota wrote:
> What's the difference between building custom kernel with Fedora and
> building a kernel with the sources from kernel.org?Building with rpmbuild
> takes way longer to build than the normal source code from kernel.org which
> is wierd.

For one thing, the Fedora kernel specfile is written to built a number
of packages, some of which might be very expensive to built (my guess
would be that the debuginfo package takes a lot of time).

> I've set it to build with rpmbuild for about 3h ago and it's still
> building taking about 90% ~ 100% of both cores.

A few months ago I posted a message
(http://lists.fedoraproject.org/pipermail/kernel/2011-February/003032.html) in which I documented the command I use to keep the Fedora kernel's rpm build time at an (for me) acceptable level:

> Just to help me remember (or rediscover) this:
>     rpmbuild -bb --target=i686 --with baseonly --without perf
> --without debuginfo $SPECS/kernel.spec
> 
> comes close. (It also generates the kernel-devel and kernel-headers
> packages, but that doesn't seem to cost much time).

A command like that one takes (roughly) one hour at a dual core, x86-64
laptop and two hours on a single core, i686 laptop. I don't build custom
kernels that often, so I haven't bothered looking for further speed
gains.


Paul Bolle