Systems runs slower after kernel recompile

Cr0wb4r · 03-08-2011, 03:47 PM

Hello,
I have been messing around with Linux for a while now and have attempted multiple kernel recompiles. Some of them have turned out good, while others have turned out down right terrible. I recently recompiled my slackware kernel, and had a massive drop in my quake 3 frame rate. I have tried both the old and the new kernel and the generic one runs better. Are there some basic rule or tips that will help me optimize my kernel?
Any tips/tricks would be greatly appreciated.
Thanks in advance.

andrewthomas · 03-08-2011, 03:55 PM

If a generic kernel is working better than a custom one then you are leaving something out of your .config.

You should have a look at Pappy's excellent site.

This page in particular - http://kernel-seeds.org/working.html

follow the instructions and enter your info into the Debian GNU/Linux device driver check page, then you will know how to adapt one of the seeds to fit your system.

Cr0wb4r · 03-09-2011, 04:33 PM

Thanks I will have a look at that.

Cr0wb4r · 03-16-2011, 12:14 PM

I have another question. If I recompile a generic kernel, leaving the configuration alone so that it has all of the default values. Will I still increase my performance, or do I have to remove unnecessary stuff to get that?

TobiSGD · 03-16-2011, 12:59 PM

If you compile two kernels with the same .config, why do you suppose to get two different kernels? Of course there are the same. If you cook two meals with the same receipt you also will get the same meals, won't you?
Exactly that is the point of optimizing a kernel. Keep what you need, get rid of what you don't need. After that, tweak the settings.

Cr0wb4r · 03-16-2011, 02:22 PM

@ TobiSGD
Right, what I meant was do you gain anything by simply compiling the kernel on you own system vs the default installed one?

TobiSGD · 03-16-2011, 02:34 PM

If you use the same .config you gain exactly nothing.