Comer - Essentials of computer architecture

ESSENTIALS OF
COMPUTER ARCHITECTURE

Second Edition

Second Edition

DOUGLAS COMER

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Library of Congress Cataloging-in-Publication Data

Names: Comer, Douglas, author.
Title: Essentials of computer architecture / Douglas Comer.
Description: Second edition. | Boca Raton : Taylor & Francis, a CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa, plc, [2017] | Includes index.
Identifiers: LCCN 2016041657 | ISBN 9781138626591 (hardback : alk. paper)
Subjects: LCSH: Computer architecture.
Classification: LCC QA76.9.A73 C625 2017 | DDC 004.2/2--dc23
LC record available at https://lccn.loc.gov/2016041657

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To Chris, who makes all the
bits of life meaningful

Hardware engineering has shifted the use of discrete electronic components to the use of programmable devices. Consequently, programming has become much more important. Programmers who understand how hardware operates and a few basic hardware principles can construct software systems that are more efficient and less prone to errors. Consequently, a basic knowledge of computer architecture allows programmers to appreciate how software maps onto hardware and to make better software design choices. A knowledge of the underlying hardware is also a valuable aid in debugging because it helps programmers pinpoint the source of problems quickly.

The text is suitable for a one-semester undergraduate course. In many Computer Science programs, a course on computer architecture or computer organization is the only place in the curriculum where students are exposed to fundamental concepts that explain the structure of the computers they program. Unfortunately, most texts on computer architecture are written by hardware engineers and are aimed at students who are learning how to design hardware. This text takes a different approach: instead of focusing on hardware design and engineering details, it focuses on programmers by explaining the essential aspects of hardware that a programmer needs to know. Thus, topics are explained from a programmers point of view, and the text emphasizes consequences for programmers.

The text is divided into five parts. covers the advanced topics of parallelism, pipelining, power and energy, and performance.

describes an important aspect of the course: a hands-on lab where students can learn by doing. Although most lab problems focus on programming, students should spend the first few weeks in lab wiring a few gates on a breadboard. The equipment is inexpensive (we spent less than fifteen dollars per student on permanent equipment; students purchase their own set of chips for under twenty dollars).

provides a quick introduction to x86 assembly language and the x64 extensions. Many professors teach x86 and have requested that it be included. The material is in an appendix, which means that professors who choose to focus on a RISC assembly language (e.g., the ARM architecture) can use it for comparison.

The second edition contains two new chapters as well as changes and updates throughout. on power and energy covers the basics without going into detail. It explains why a dual-core chip in which each core runs at half speed takes less power than a single core chip that runs at full speed.

We have set up a Web site to accompany the book at:

http://www.eca.cs.purdue.edu

The text and lab exercises are used at Purdue; students have been extremely positive about both. We receive notes of thanks for the text and course. For many students, the lab is their first experience with hardware, and they are enthusiastic.

My thanks to the many individuals who contributed to the book. Bernd Wolfinger provided extensive reviews and made several important suggestions about topics and direction. Professors and students spotted typos in the first edition. George Adams provided detailed comments and suggestions for the second edition.

Finally, I thank my wife, Chris, for her patient and careful editing and valuable suggestions that improve and polish the text.

Douglas E. Comer

Dr. Douglas E. Comer, PhD, has an extensive background in computer systems, and has worked with both hardware and software. Comers work on software spans most aspects of systems, including compilers and operating systems. He created a complete operating system, including a process manager, a memory manager, and device drivers for both serial and parallel interfaces. Comer has also implemented network protocol software and network device drivers for conventional computers and network processors. Both his operating system, Xinu, and TCP/IP protocol stack have been used in commercial products.