I've been playing around with Linux for a few years now and my goal is to have an ultra-lean, specialized kernel for my laptop. I know that most Linux users don't go through the trouble to do this, but I know that there have to be people out there as anal as I. Despite having played around with Gentoo and having perused the LFS documentation, I can't seem to find a source that will tell me how to figure out EXACTLY what kernel configuration is optimal for my system. I realize that no one's going to just tell me how what configuration is optimal for my system... what I'm looking for is guidance on how to do it myself. Thanks ahead of time to anyone who can give me some insight.

Hi.

There's not much to it. Start from an 'everything off' situation, then just pick the right processor type and add only what you need.

My advice would generally be to compile-in anything that can't be hot-plugged (PCI card drivers, system FS types etc), and compile anything else you need as a module (USB device drivers, FAT32 etc).

Dave

Certain things are dependent on the way you use your system, like scheduling. Choosing the right option will require knowledge of the situation when a certain option should be used and a little while of thinking if it fits your case. If you want to know more, I recommends getting a book about general kernel design (doesn't have to be Linux--specific, rather show the basic and more advanced concepts).

I guess what I'm really asking is: How do I determine hardware dependencies for my devices?

Run up Knoppix, and "lsmod".
Good a place as any to start.

One thing I did to fully customize my kernel is read the kernel log file (perhaps /var/log/kernel.log, the name changes from one distro to the next). Find a spot in the log where a reboot starts, start reading from there. You might find a module saying something like "exiting, hardware not found". You now know that the module can be left out of your kernel. Just keep on reading, take note of the names of devices that were properly set up.

Since many distros make kernels that enable just about every module, you should have a pretty decent list of hardware+modules when you are done.

I agree with ilikejam about statically compiling more "constant" things, and leaving others as modules. Good advice.

Finally, there is "lspci -vv", and lsusb. They'll give you a good idea of what you need in your kernel.

HTH
peart.

PS: Expect to fsck up your first few kernels. Keep a working one handy!