Linux Internals

Rating:
Summary: In-depth, but skipping the basics
Review: As the introduction to the book says (by a RedHat kernel developer), this book is a "reference work to be used to look up the Linux Kernel concepts." The author mostly breezes through the basics and jumps right into the source code and hi-powered concepts such as SMP.

For a primer to the Linux source code and concepts, I found "Linux Kernel Internals" by M. Beck et al. far more useful (although it only covers Linux 2.0). That book goes through such procedures as compiling and debugging the kernel, which I really needed to know. This is not to discredit "Linux Internals", it just seems like the two books target different audiences.

Rating:
Summary: Badly organized and edited
Review: Here are some examples of the errors in this book; I gave up on it around page 50. It tries to distinguish between RISC and CISC but gets them backwards. Most of the underscores in the code listings have been replaced by spaces. It states that linked lists and arrays are the same thing. A table refers to the "Bite size" of processor architectures. Structurally, it jumps quickly into a deep description of x86 instruction scheduling without explaining why. There's some useful information in there, if you can find it through the errors and poor organization. There are better books on the topic.

Rating:
Summary: Stay away from this book
Review: I've only read the first three chapters of this book, and I've already spotted so many errors that I don't think I'll continue. After spotting so many mistakes I have to wonder how many mistakes I'm not catching. Some of these mistakes are obviously typographical errors (which could be excused if not for the price), but there are several statements that are simply wrong. At best, these errors cause confusion, and I'm left second guessing the book. At worst, I'm worried about how much misinformation I might be "learning" from this book.

Rating:
Summary: Excellent for Kernel Beginners
Review: Previous to this book I did not know what makes a Linux kernel. Sure, I had read various articles here and there. But this book really explained the inner workings of the new Linux 2.4.0 version to me in easy language. I had to read it several times because some of the concepts of kernels really are challenging, at least to me. Now, I know where to go look in the source code whenever I want to get deeper knowledge.

The author did a good job explaining even elementary kernel funcitonality and basic OS theory. The part on journalling file systme is the first comprehensible explanation of the subject I have seen.

Rating:
Summary: Mixed Feelings
Review: This book is a mess. It does not appear to have been seen by a copy editor, as it is full of spelling mistakes and figure captions like "Please provide figure caption."

It is also full of mistakes; even sample code is terribly defective, and wouldn't even compile properly with recent kernels. As one trivial example, the return type of the function "cleanup_module()" is given as an "int" instead of a "void".

A large fraction of the book is given over to pasting in large sections of the Linux kernel source; I wouldn't be surprised if these pages were one third of the total. Given the fact that the kernel source changes all the time, this code was already out of date when the book was published. (This wouldn't be a problem if the author had restricted himself to a stable production kernel of the 2.2 series, but the 2.4 kernel is prominently advertised on the cover.) This wholesale lifting and publishing of unaltered kernel code may not violate the GPL, but it is idiotic as any one following Linux kernel development knows one always has to look at the source itself to be accurate.

I believe the wholesale inclusion of out of date source was done to pad out this rather flimsy book.

Overall the author's discussion is incomprehensible, without any clear plan. I feel sorry for Ingo Molnar who must have been duped into writing a forward; surely someone of his talent could not have looked at the whole book and said something positive.

Don't buy this book. Complain to the publisher that Linux is not well served by the publication of pasted together quickie books.

This book is worse than worthless; it is misleading and inaccurate.

Rating:
Summary: In-depth, but skipping the basics
Review: This book is not a good reference for kernel internals in Linux. It has a very superficial treatment of the majority of topics. If you're expecting to use this book like the famous UNIX "Magic Garden", forget it. This book does not have any depth.

Rating:
Summary: Very disorganized, careless, but not useless
Review: This book started with incredibly many typos (and some errors). A lot of important details that I was looking for was just not explained. The author might have tried, but didn't spend enough time to make it crystal-clear. It was really amazing how some chapters have so little written, but were appended with a lot more pages of unexplained kernel (C language) header. A lot of the other material seem to be simply cut and paste from other sources.

I did learn a bit from this book after reading it through, out of desperation - without another Linux Kernel book in my hand. I still don't feel I understand what I was expecting from this book. I don't think it is worth the listed price. I think it is worth $... Not to say, a lot of the material is already out-dated, even for the 2.3 kernel.

Rating:
Summary: Unedited garbage
Review: This book was not edited. I believe they folded up the second draft and mailed it to bookstores. The author is also a very poor writer. Portions of the text remind me of the "All your base are belong to us" funnies or similar jokes about bad translations. I recommend that no one buy it; that the author be vigorously slapped with a large wet fish; and that the publishers and editors be exiled to some land without books or paper.

This is the worst technical book I have EVER purchased.

Rating:
Summary: Just what I needed
Review: This is a book for people who want to have an overall understanding of the Linux kernel 2.4 without wanting to know each and every function name by heart. It shows how the main components work and what the design decisions were behind them. The source code in each chapter makes it easy to check with what is explained. You must know the Linux basics, though (as Bar says in the introductory chapter), to be able to keep up with the author.

Overall a very good book and it sure helped me grasp just what the Linux kernel is about. Al Stevens of Dr. Dobbs Journal likes the book, too by the way.

Rating:
Summary: a readable/informative book on selected kernel topics
Review: This is a surprising readable book considering that highly technical topics such as this are often difficult to write about. It is certainly a much better read than the other books about the Linux kernel currently in print. As the author points out in the preface, this book is not intended as a full source code commentary of the kernel, rather it focuses upon describing those parts of the kernel that are relevant to performance issues of the OS and user applications. Certainly some esoteric topics of particular interest to kernel hackers are likely missing but on the other hand more practical topics such as filesystems (including JFS and LVM) and signal handling are well covered.

The author's writing style can be a bit obtrusive at times and it would have been nice if a good technical editor had also corrected some of the more glaring errors such as "next'ed" instead of "nested" or the overuse of the adverb "excellently". The extracts of code from the kernel are generally well selected and short enough to comprehend along the with associated discussion.

Overall, I would recommend this book to someone already knowledgeable with Linux and familiar with C programming who would like to obtain a better grasp of how the kernel is designed and what the resulting implications are for the performance of the system.