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Linux: Custom Kernels Trim Fat and Tune Performance

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Linux

I have some shocking news: despite the astonishing growth of Linux, there is a whole new generation of Linux users who have never, ever compiled a kernel. How to account for this sad state of affairs? Perhaps it's because the distribution maintainers are doing such fine jobs it's not necessary. Maybe users just don't know that they can. Whatever the reasons, today we're taking a tour of some of the different ways to customize the Linux kernel. First we'll learn the old reliable generic way, and then take a tour of the Fedora Way and the Debian Way of customizing kernels.

A word of warning: while building a custom kernel isn't all that difficult, it is complex and time-consuming, and when you're all finished you might be the proud parent of a non-booting kernel. The good news is you can have as many do-overs as you want without hurting your system. Any Linux system can have any number of kernels and you can choose which one to boot to, so never delete old kernels until you're certain your new one works correctly. Your system will not try to boot to a new kernel until you explicitly configure it to do so, so it can't sneak up on you. So you can go on a wild spree and build and test a whole army of new kernels if you like.

Give yourself a couple of gigabytes of disk space to play with...

Why would you even want to do this?

Full Story.




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