6/19/2007se 652- 2007_06_19_overview_inspections.ppt1 team software project (tsp) june 19, 2007 high...

6/19/2007 SE 652- 2007_06_19_Overview_Inspections.ppt 1

Team Software Project (TSP)

June 19, 2007

High Level Designs,

Code Inspections &

Measurement


Outline

High Level Design Phase Review

Inspection Questions

Power

Code Inspection

Measurement

System Test Plan Review

Next Phases (Implementation & Test)


Due Today

Completed & Inspected High Level Design (SDS) & Integration Test Plan

Completed & Inspected Configuration Management Plan

SRS Inspection Quality Records (LOGD, INS, Baseline Sheets)

Completed & Inspected Integration Test Plans (incl. LOGD, INS, Baseline forms)

Completed and Inspected Coding, naming & design standards (incl. LOGD, INS, Baseline forms)

System Test Plans (draft for inspection)

Updated project schedule & measurement data collected

Time, defect & size data collected

Updated project notebook


Software Design Specification (SDS)

InputConceptual Design

Requirements (SRS)

Design ObjectivesPrincipal parts

How the parts interact

How they are put together


Design Standards

Naming conventionsFunction, File, Variable, Parameter NamesDefines, Globals, Public, Statics, etc.

Interface formatsVariable handlingError codes

System & Error messagesDefect standards

SeveritiesDefect typesRoot cause bucketing

LOC counting


Design for Reuse

Reusable functions should be:Self contained

Cleanly isolated

Clearly & concisely documented (usage, interfaces, returns, errors)

Examples of successful reusable components?


Design for Testability

Unit test harnesses

Simulation testing

Black box testingVerify program’s external interfaces

White box testingAlso considers program’s logical paths & structure

Typically requires special tools (e.g. code coverage)

Typically requires supporting code


Integration Test Plan

ObjectiveVerify all system component interfaces

ActivityReview all interfaces (as defined in SDS)

Specify how to test them

Recommend: inspecting SDS & Integration Test Plan simultaneouslyCould also combine into a single document


System Test Plan

Areas to cover:InstallationStart-upAll required functions available & working as specifiedDiabolical (e.g. power failures, corner cases, incorrect handling)PerformanceUsability

Includes:Test cases you plan to run (numbered / named)Expected resultsOrdering of testing & dependenciesSupporting materials neededTraceability to requirements


Power!

What is it?“probability that one actor within a social relationship will be in a

position to carry out his own will despite resistance” – Max Weber

“interpersonal relationship in which one individual (or group) has the ability to cause another individual (or group) to take an action that would not be taken otherwise” – Steers & Black


Types of Power

Referent/CharismaticBased on personal qualities, characteristics, reputation

ExpertKnowledge or expertise relevant to person

Power only in domain of expertise

LegitimatePerson has the right to exert power in a specified domain

RewardControls rewards a person wants

CoerciveBased on fear, person can administer punishment


Effectiveness

Which types of power are most effective?

Power within the class teams?


Inspections

Inspection ObjectivesFind defects at earliest possible pointVerify to specification (e.g. design to requirements)Verify to standardsCollect element and process dataSet baseline point

Exit CriteriaAll detected defects resolvedOutstanding, non-blocking issues tracked

Techniques & MethodsGeneric checklists & standardsInspectors prepared in advanceFocus on problems, not on resolutionPeers only“Mandatory” data collection

Roles: Moderator, reader, recorder, inspector, author


Inspection Logistics

Identify moderator (for TSPi, use process manager)Inspection briefing (identify inspection roles, set date/time for inspection)Review product

– Individual reviews– Record time spent reviewing– Identify defects, but do not log on LOGD form

(defects recorded during inspection on INS & LOGD forms)

– Typically want 3-5 days for an adequate review period

Inspection meeting– Obtain & record preparation data– Step through product one line or section at a time– Raise defects or questions– Defects recorded by moderator on INS form– Defects recorded by producer on LOGD form (no need to use Change Requests)– Peripheral issues & action items should be recorded in ITL log*


Inspection Logistics (continued)

Estimate remaining defectsTBD (but, for each defect, record all members who identified it)

Conclude meeting– Agree on verification method for defects

– Agree on disposition (e.g. approved, approved with modification, re-inspect)

Rework product & verify fixes (e.g. moderator)

Obtain signatures of all inspectors on baseline sheet(file as quality record)

Spelling Code Inspection


Measurement Data & Metrics

Base Metrics# & Type of Defects found (major, minor)For each defect, who found# of pages inspected, preparation time (per inspector), inspection time

MeasuresPreparation rate = # pages / average preparation timeInspection rate = # pages / inspection timeInspection defect rate = # major defects / inspection timeDefect density = # estimated defects / # of pagesInspection yield = # defects / # estimated defects (individual & team)

SRS Phase Defect Containment (%) =100% * # Defects removed @ step / ( Incoming defects + Injected defects)


InspectionsEstimating Defects

Capture-ReCapture ExampleCatch 20 fish in lake, tag & release them

Catch 25 more, 5 are tagged

How many fish are in the lake?

5 out of 25 = 20 out of Total Population

Total = ?


Capture-ReCapture Formula

Fishing example:5 out of 25 = 20 out of Total

C = # from both fishing tries (e.g. 5)

A = # from first fishing try (e.g. 20)

B = # from second fishing try (e.g. 25)

So,C out of B = A out of Total

C/B = A/Total

Total = A*B/C


Estimating Defects2 Developer Case

C = # from both tries = # found by both developersA = # from first try = # found by developer AB = # from second try = # found by developer B

Total # defects = # A * # B / # both foundYield = # found / Total # defects expressed as percentage

= 100 * (A*B-C) / (A*B/C)= 100 * (A*B-C)*C / A*B

Humphrey 2 Developer Example:Two developers, A found 7, B found 5, common defects 3Total estimated # defects = (7*5)/3 = 12Yield = 9 / 12 = 75%


Estimating Defects3 Developer Example

Three developers in an inspection identified 10 unique defects (# from 1 to 10).Harry found defects 1, 2, 3, 4 & 5

Chapin found defects 1, 2, 4, 6 & 7

Sue found defects 4, 6, 7, 8, 9 & 10

Estimate total # of defects in product prior to inspection.

Estimate total inspection yield.

Sue identified the most unique defects (3) = 6 identified

Combine Harry’s & Chapin’s defects = 7 identified, 3 in common w/ Sue

Total Product Defects = 6 * 7 / 3 = 14

Yield % = 100 * 10/14 = 71%


Capture-ReCapture Assumptions & Cautions

• Population is homogeneous

• Population is randomly distributed

• Sample #s are reasonably large

Backup Slides

6/19/2007se 652- 2007_06_19_overview_inspections.ppt1 team software project (tsp) june 19, 2007 high...

Documents

test cases

black slide

supporting code slide

ppt7 design

ppt6 design

ppt9 system test plan

naming design standards

ppt5 design standards