Transcript Software Inspections

Design and Code Inspections to Reduce
Errors in Program Development.
M.E. Fagan
IBM Systems Journal, 1976
Presented by
Ankush Varma
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Overview
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What is Code Inspection
Study: Quantification of Benefits
The Formal Inspection Process
Code Inspection for Process Management
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Code Inspection
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Code is only looked at from a
debugging viewpoint.
Cannot revisit algorithms,
check for coding standards
etc. easily.
Inspection is a formal process
of looking at all aspects of
both design and code even
when nothing seems broken.
Write Code
Debug
Test
Add features
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Programming : A Manageable Process
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Programming can be though of as a process:
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Requirement Statements are Input.
A series of processing operations act on this.
Each step has well-defined output.
Each step has unambiguous exit criteria e.g. clean
compilation, number of lines of code a design
statement translates to etc.
Cost of reworking errors massively increases down the
process.
Note the underlying ties to a waterfall model.
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The Programming Process
cost
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The Benefits of Code Inspection : A Study
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Study of Error Detection Rates
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The Formal Inspection Process
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People Involved
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Moderator
Designer
Coder/Implementor
Tester
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The Steps of the Inspection Process
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What to Look For : Examples
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Code Inspection for Process Management
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Using Code Inspections for Process Control
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List most error-prone modules to prioritize testing,
re-coding or later inspections.
Compare processes to evaluate relative
effectiveness.
Use increased predictability to plan ahead.
Error re-work moved to first half of process,
where it is cheaper.
Earlier quantification of product quality.
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Inspections are NOT Walk-Throughs
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Questions/Discussion
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