Understanding the Linux Kernel Book

Understanding The Linux Kernel is intended to be read by those happy to check points off against the source code. The first thing you learn is how, released from commercial constraints, Linux is able to take advantage of the best ideas from other systems implemented in wonderfully flexible ways. A good example is the Virtual File System. VFS has made it easy to add support for file systems from almost every other operating system. It is fascinating to find out how such features are implemented. Then there are loadable modules, I/O, scheduling, multitasking, multiprocessing, interrupts, spin locks, semaphores and all the other goodies involved in making a kernel work.The authors are primarily concerned with the Linux 2.2 kernel. They discuss how Linus Torvald's decisions on kernel issues translate into architecture, for example, how the Linux' memory management uses a Slab Allocator on top of a Buddy System for greater efficiency. Similarly, at the cost of a little complexity the decision to use three-level memory paging when two work fine on 32-bit systems makes it possible to port to 64-bit processors without changes. The trade-offs between complexity and efficiency are discussed for most kernel features and each chapter finishes with related new features in kernel 2.4.Despite the lucid and knowledgeable writing, you will come up against some brain-stretching complexity. Nevertheless, this is an important addition to the Linux canon. --Steve PatientRead More