Book Image

Mastering Linux Kernel Development

By : CH Raghav Maruthi
Book Image

Mastering Linux Kernel Development

By: CH Raghav Maruthi

Overview of this book

Mastering Linux Kernel Development looks at the Linux kernel, its internal arrangement and design, and various core subsystems, helping you to gain significant understanding of this open source marvel. You will look at how the Linux kernel, which possesses a kind of collective intelligence thanks to its scores of contributors, remains so elegant owing to its great design. This book also looks at all the key kernel code, core data structures, functions, and macros, giving you a comprehensive foundation of the implementation details of the kernel’s core services and mechanisms. You will also look at the Linux kernel as well-designed software, which gives us insights into software design in general that are easily scalable yet fundamentally strong and safe. By the end of this book, you will have considerable understanding of and appreciation for the Linux kernel.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Process priorities


The decision of which process to run depends on the priority of the process. Every process is labelled with a priority value, giving it an immediate position in terms of when it will be given CPU time. Priorities are fundamentally classified into dynamic and static priorities on *nix systems. Dynamic priorities are basically applied to normal processes dynamically by the kernel, considering various factors such as the nice value of the process, its historic behavior (I/O bound or processor bound), lapsed execution, and waiting time. Static priorities are applied to real-time processes by the user and the kernel does not change their priorities dynamically. Processes with static priorities are thus given higher priority when scheduling.

Note

I/O bound process: When the execution of a process is heavily punctuated with I/O operations (waiting for a resource or an event), for instance a text editor, which almost alternates between running and waiting for a key press, such processes...