The focus of this little book is the performance of selected components of operating systems. It is intended as a “Performance Supplement” to operating systems texts. The description of every problem starts with an analogy from everyday life: a hamburger restaurant with customers, lines, counters, workers, and so on is given as an example for multiple station waiting queues.
Six topics are treated, each of them with variants differing with respect to service speed or policy: single station waiting queues, multiple station waiting queues, processor scheduling, disk scheduling, process synchronization (mutual exclusion), and memory management. For each problem, a tiny model is presented and analyzed using a single modeling technique: Markov chains. In most cases, the balance equations are written down explicitly and the steady state solution is given by means of formulas or as figures in a lengthy table. From this, the authors calculate performance measures, which serve for comparing the variants of the systems.
Many important notions and concepts of performance evaluation are introduced in a simple and clear fashion. All definitions and explanations are informal, and the accuracy is not always satisfactory. The mathematical techniques--steady state solutions of discrete and continuous time Markov chains--are applied without hesitation. No mathematical theory is mentioned, and the authors do not even remark on the limits of the techniques. This omission is the main drawback of the book.
The references are few, and the index is incomplete. The authors do not recommend this book as a textbook for a first course in performance evaluation; they are right, as many important techniques and topics are not dealt with. The main objective of the book, namely to increase the “performance awareness” of computer science students, is met, however. The writing style is simple, and the level of ambition is low. The book is suited for third-year students who have a basic knowledge of computers, operating systems, calculus, linear algebra, and probability. Adequate exercises are included.
