PSP(sm): A Self-Improvement Process for Software Engineers (SEI Series in Software Engineering)

373 Pages·2005·2.26 MB·English

by  Watts S. Humphrey

PSPSM
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PSPSM
A Self-Improvement Process
for Software Engineers
Watts S. Humphrey
with Support Tool by
James W. Over
Upper Saddle River,NJ • Boston • Indianapolis • San Francisco
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The SEI Series in Software Engineering
Many of the designations used by manufacturers and sellers to distinguish their products are claimed
as trademarks. Where those designations appear in this book,and the publisher was aware of a trade-
mark claim,the designations have been printed with initial capital letters or in all capitals.
CMM,CMMI,Capability Maturity Model,Capability Maturity Modeling,Carnegie Mellon,CERT,
and CERT Coordination Center are registered in the U.S. Patent and Trademark Office by Carnegie
Mellon University.
ATAM; Architecture Tradeoff Analysis Method; CMM Integration; COTS Usage-Risk Evaluation;
CURE; EPIC; Evolutionary Process for Integrating COTS Based Systems; Framework for Software
Product Line Practice; IDEAL; Interim Profile; OAR; OCTAVE; Operationally Critical Threat,Asset,
and Vulnerability Evaluation; Options Analysis for Reengineering; Personal Software Process; PLTP;
Product Line Technical Probe; PSP; SCAMPI; SCAMPI Lead Appraiser; SCAMPI Lead Assessor;
SCE; SEI; SEPG; Team Software Process; and TSP are service marks of Carnegie Mellon University.
Special permission to reproduce “PSP process materials”(©2004 by Carnegie Mellon University) is
granted by the Software Engineering Institute.
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plied warranty of any kind and assume no responsibility for errors or omissions. No liability is assumed
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Library of Congress Cataloging-in-Publication Data:
Humphrey,Watts S.,1927–
PSP :a self-improvement process for software engineers / Watts S. Humphrey.
p. cm. — (The SEI series in software engineering)
Includes bibliographical references and index.
1. Software engineering. 2. Computer software—Management. I. Title. II. Series.
QA76.758.H8624 2005
005.1—dc22 2004030348
Copyright ©2005 Pearson Education,Inc.
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ISBN 0-321-30549-3
Text printed in the United States on recycled paper at Courier in Westford,Massachusetts.
First printing,March 2005
IN MEMORY OF DR. JOHN E. YARNELLE
an inspiring teacher
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CONTENTS
PREFACE XIII
Chapter 1 THE PERSONAL PROCESS STRATEGY 1
1.1 The PSP’s Purpose 3
1.2 The Logic for a Software Engineering Discipline 4
1.3 Using Disciplined Development Practices 6
1.4 Operational Processes 6
1.5 Defining and Using a Personal Process 7
1.6 Learning to Use a Personal Process 8
1.7 Preparing for the Team Software Process 9
1.8 Summary 9
Reference 10
Chapter 2 THE BASELINE PERSONAL PROCESS 11
2.1 What Is a Process? 12
2.2 Defining Your Own Process 13
2.3 Baseline Process Contents 14
2.4 Why Forms Are Helpful 16
2.5 The PSP Process Elements 17
2.6 The PSP0 Process 18
2.7 PSP0 Measures 20
2.8 Time Recording 21
vii
viii Contents
2.9 Defect Recording 24
2.10 The PSP0 Project Plan Summary 30
2.11 The Compile Phase 31
2.12 Incremental Development 32
2.13 PSP Tool Support 34
2.14 Summary 34
2.15 Exercises 34
Chapter 3 MEASURING SOFTWARE SIZE 35
3.1 Size Measures 35
3.2 Establishing a Database Counting Standard 40
3.3 Establishing a Line-of-Code Counting Standard 40
3.4 Size Accounting 42
3.5 Using Size Data 45
3.6 Calculating Productivity 47
3.7 Size Counters 48
3.8 Other Size Measures 53
3.9 Summary 54
3.10 Exercises 54
References 55
Chapter 4 PLANNING 57
4.1 The Planning Process 58
4.2 Why Make Plans? 59
4.3 What Is a Plan? 60
4.4 The Contents of a Software Plan 60
4.5 Planning a Software Project 62
4.6 The Conceptual Design 63
4.7 Plan Quality 65
4.8 Planning Issues 65
4.9 Summary 66
Reference 67
Contents ix
Chapter 5 SOFTWARE ESTIMATING 69
5.1 Size Estimating Principles 69
5.2 The Conceptual Design 70
5.3 Proxy-Based Estimating 71
5.4 Using Proxies in Estimating 75
5.5 Producing the Relative-Size Table 78
5.6 Estimating Considerations 80
5.7 Summary 84
Chapter 6 THE PROBE ESTIMATING METHOD 85
6.1 Estimating from Data 85
6.2 Proxy-Based Estimating 87
6.3 Estimating with Limited Data 95
6.4 An Estimating Example 100
6.5 Estimating Nonprogramming Tasks 102
6.6 Considerations in Using PROBE 105
6.7 Summary 108
6.8 Exercises 108
Chapter 7 SOFTWARE PLANNING 109
7.1 Plan Requirements 109
7.2 Project and Period Plans 111
7.3 Producing the Schedule 113
7.4 Making the Schedule 115
7.5 Earned Value 119
7.6 An Earned Value Example 120
7.7 Comments on the EV Example 123
7.8 Estimating Accuracy 125
7.9 The Prediction Interval 126
7.10 Alerting Management to Changes 128
7.11 Planning Considerations 129
7.12 Summary 131
7.13 Exercises 132
References 132