Chapter 33. Modifying the Linux Kernel to Improve Performance

In This Chapter

• Download and Install the Kernel Sources Package

• Kernel Modules

• Creating a Custom Kernel

• Updating GRUB

• Updating the Kernel Using RPMs

• Conclusion

Like a government that rules a nation and all its provinces, the Linux kernel is the central program that not only governs how programs interact with one another, but also provides the guidelines on how they should use the computer's core infrastructure, such as memory, disks, and other input/output (I/O) devices for the user's benefit.

Linux drivers, the programs that manage each I/O device, are the staff that keeps all the government departments running. Continuing with the analogy, the more departments you make the kernel manage, the slower Linux becomes. Large kernels also reduce the amount of memory left over for user applications. These may then be forced to juggle their memory needs between RAM and the much slower swap partitions of disk drives, causing the whole system to become sluggish.

The Fedora installation CDs have a variety of kernel RPMs, and the installation process autodetects the one best suited to your needs. For this reason, the Fedora Linux kernel installed on your system is probably sufficient. The installation process chooses one of several prebuilt kernel types depending on the type of CPU and configuration you intend to use (Table 33.1).

Table 33.1. Kernels Found on Fedora Installation CDs

Processor Type	Configuration
I586	Single processor
I586	Multiprocessor (SMP)
I686	Single processor
I686	Multiprocessor (SMP)