1SE-280Dr. Mark L. Hornick

In software engineering, we sometimes distinguish between "practice" and "process".

By "practice", we mean "what" software engineers do (e.g., analyze

requirements, create architectural and detailed designs, implement, verify).

By "process", we mean "how" software engineers do their work (e.g., plan, organize,

measure, make and meet commitments, ensure quality, control, improve, adapt).

What do software engineering managers say they most want from software developers and teams?

What do software engineering managers say they most want from software developers and teams?

Predictability

Quality

4SE-280Dr. Mark L. Hornick

If I were to give you a requirements specification for a medium-sized program, could you tell me in advance . . .

. . . how long it would take you to write the program?

. . . how many defects you would inject during its development?

. . . how many defects will remain when it is completed?

Who are these people?

6SE-280Dr. Mark L. Hornick

Why do we need a Process?

Many developers do not know how to estimate

Management sets aggressive goals

Marketing makes promises to customers

7SE-280Dr. Mark L. Hornick

Why do we need a Process?

Many organizations today cannot meet commitments with repeatability Project A completes without any problems Project B is a disaster

Late Incomplete Not tested

Too many times, the result is Cancelled projects Management over-reaction

What is your current software development process? What is good and bad about it?[Group exercise]

9SE-280Dr. Mark L. Hornick

In this course, you will gain experience in using a defined software process and measuring your own performance.

The Personal Software Process (PSP) is designed to allow individual software engineers to improve their own work.

The Team Software Process (TSP) builds on the PSP to help self-directed software engineering teams to deliver high-quality

products on predictable schedules.

10SE-280Dr. Mark L. Hornick

The PSP and TSP were developed by Watts Humphrey at the Software Engineering Institute (SEI).

In 2005, Humphrey was awarded the National Medal of

Technology for his work in software process

improvement.

11SE-280Dr. Mark L. Hornick

Industry experience shows that the TSP can help teams achieve high levels of quality.

7.5

6.24

4.73

2.28

1.05

0.060

1

2

3

4

5

6

7

8

Level 1 Level 2 Level 3 Level 4 Level 5 TSP

Defects/KLOC

Total Delivered Defects/KLOC

N. Davis and J. Mullaney, The Team Software Process (TSP) in Practice: A Summary of Recent Results, Technical Report CMU/SEI-2003-TR-014, www.sei.cmu.edu/publications/.

12SE-280Dr. Mark L. Hornick

[Source: AIS]

Schedule Deviation Individual Value Control Chart - Commercial Systems

-150-100

-500

50100150

200250

300350

01/8801/89

01/9001/91

01/9201/93

01/9401/95

01/9601/97

01/98

Date of Project Start

% D

ev

iati

on

Individual Data Points Mean Upper Natural Process Limit

Lower Natural Process Limit One Standard Deviation

CMM introduced

TSP introduced

By increasing predictability, the TSP helps teams to function more effectively.

13SE-280Dr. Mark L. Hornick

Data from PSP training courses show similar results for practicing software engineers and MSOE SE students.

Total Defect Density (SEI)

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ects

/KL

OC Max

75pct

Avg

25pct

Min

SEI: 810 engineers MSOE: 83 sophomore students

Total Defect Density (MSOE)

0.0

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ects

/KL

OC Max

75pct

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Min

14SE-280Dr. Mark L. Hornick

Yield is a measure of the percentage of defects removed by a specified point in the process.

Yield Before Compile (SEI)

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ld (

%)

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Yield Before Compile (MSOE)

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ld (

%)

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Min

SEI: 810 engineers MSOE: 83 sophomore students

15SE-280Dr. Mark L. Hornick

Testing time is a major cost in commercial software development; PSP course data shows a reduction in test time.

Test TIme % (SEI)

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Ime

%

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Test TIme % (MSOE)

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ime

%

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25pct

Min

SEI: 810 engineers MSOE: 83 sophomore students

16SE-280Dr. Mark L. Hornick

Even with additional PSP planning and quality activities, overall productivity remains nearly constant.

Productivity (MSOE)

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Productivity (SEI)

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SEI: 810 engineers MSOE: 83 sophomore students

17SE-280Dr. Mark L. Hornick

You can improve your own performance as a software engineer using disciplined methods, but it does take some effort.

MSOE sports photos courtesy of Dr. Eric Durant

18SE-280Dr. Mark L. Hornick

Please complete the following assignment before the start of the next class.

Read textbook pages 1-34. Download the Process Support Tool from

the course website Log into SVN to verify that you are set up

correctly https://emerald.msoe.edu/svn/se280-<your-name> Ask right away if you have problems or questions

about SVN Bring your notebook computers to class

19SE-280Dr. Mark L. Hornick

Here are a few references on SE process, PSP, and TSP.

W. Humphrey, PSP – A Self-Improvement Process for Software Engineers, A-W, 2005

W. Humphrey, Introduction to the Team Software Process, A-W, 2000 W. Humphrey, Winning with Software: An Executive Strategy, A-W, 2002 N. Davis & J. Mullaney, The Team Software Process in Practice: A

Summary of Recent Results, SEI, 2003 SEI/CMU-2003-TR-014 (www.sei.cmu.edu)

D. Suri and M. Sebern, “Incorporating software process in an undergraduate software engineering curriculum: challenges and rewards”, Proceedings of CSEE&T’04, 2004

M. Sebern, “The software development laboratory: incorporating industrial practice in an academic environment”, Proceedings of CSEE&T’05, 2005