Software Process Improvement

1
Software Process Improvement

• Lecture 12

2
Software Organization Structure
3
Three dimensions of process improvement model
Carnegie Mellon University
Capability Maturity Model
Team Software Process
Personal Software Process
4

• Capability Maturity Model (CMM)
• Quality assurance, configuration management,
  requirement management.
• Team Software Process (TSP)
• How to produce quality products on
  schedule/budget
• How to guide and support team members
• Personal Software Process (PSP)
• How to measure, estimate and improve individual
  engineers work

5
Capability Maturity Model
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Goals

• Original goal
• Defense contracts would be awarded only to
  capable firms
• Every Air Force contractor had to attain level 3
  by 1998
• The CMM has now gone far beyond the limited goal
  of improving DoD software

7
Cost and Benefits of CMM

• Hughes Aircraft (Fullerton, CA) spent 500K
  (198790)
• Savings 2M per year, moving from level 2 to
  level 3
• Raytheon moved from level 1 in 1988 to level 3 in
  1993
• Productivity doubled
• Return of 7.70 per dollar invested in process
  improvement
• Motorola GED has used CMM (199297)

8
Results of 34 Motorola Projects
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Personal Software Process (PSP) Principles

• Design a plan based on historical data
• Provide measurement for progress
• Strive to make high quality products
• Prevent defects rather than fix defects
• If defects exist, find and fix them earlier

The right way is always the fastest and cheapest
way
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PSP steps
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PSP steps

• Personal measurement (PSP0)
• gather real data (time, defects)
• introduce coding standards
• size measurement
• Personal planning (PSP1)
• estimate size and time for programs
• schedule and task planning
• Personal quality (PSP2)
• practice design and code reviews
• Scaling up (PSP3)

12
Benefits of PSP

• Reduction in estimate (size and effort) error
• Reduction in compile time and test defects
• Improvement in productivity
• More effective use of an engineers time

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Size estimation error
(Data for 300 engineers went through PSP
training from Software Engineering Institute at
Carnegie Mellon University)
14
Compile and test defects
(Data for 300 engineers went through PSP
training from Software Engineering Institute at
Carnegie Mellon University)
15
Time allocation improvement
Test
Code
Design
Compile
(Data for 300 engineers went through PSP
training from Software Engineering Institute at
Carnegie Mellon University)
16
Industry adoption of PSP

• Baan
• Boeing
• Motorola
• Teradyne
• IBM

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The Boeing company
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Benefits of PSP in academia

• Software engineers develop programming styles
  when they first learn to write programs
• Educators need to expose students to the reality
  of software development
• Students need to be prepared technically and
  professionally before entering job market

19
PSP for CS Students

• Find out their strength and weakness
• Understand reasons and benefits of good
  engineering practice
• Better understanding of software engineering
  process

20
References

• Software engineering institute at Carnegie
  Mellon University
• http//www.sei.cmu.edu/index.html
• Introduction to the Personal Software Process by
  W. Humphrey
• Software Process Dashboard Initiatives
• http//processdash.sourceforge.net/