Building a Custom Kernel

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Note:

swap space   All machines have a finite amount of Ran 

dom Access Memory. Without a method for dealing with

this limited memory the system would crash whenever avail 

able memory is exhausted. To resolve this issue, the kernel

 swaps  memory to disk when not in use, to free memory for

use by other processes. This requires a disk partition, or a

file, that has been specially formatted to deal with memory

swapping.

Building the Kernel

The Debian system provides access to the kernel in several ways. There is

a separate Kernel Image package that will allow you to install a  pre 

configured  kernel image on the current system. There is also a Kernel

Source package that will allow the custom configuration of a kernel and build

a Kernel Image package as its output.

There are no preconditions in a Debian system that require you to use these

packages. The kernel for a Debian system can be built without these packages

and will work just as well. A discussion of how to do this will be instructive

to more than just the paranoid individual who needs direct control over such

important matters as a kernel. The following section will first describe how

to construct and install a kernel without using the Debian packages, followed

by a description of the differences and advantages of using the Debianized

versions. As there are trade offs for either approach the choice of method will

be dictated by local considerations.

Non Debian Kernel Construction

Sometime before the advent of the 2.0 kernel the old method of building the

kernel was abandoned. What was removed was the requirement that the ker