Software Project Management lecture 10
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The document provides an overview of software integration and testing. It discusses integration approaches like top-down and bottom-up integration. It also covers various types of testing like unit testing, integration testing, system testing, and user acceptance testing. The document discusses test planning, metrics, tools, and environments. It provides details on defect tracking, metrics, and strategies for stopping testing.
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Performance Metrics
Source: Athens Consulting Group
Bad Good
Must support 500 users Must support 500
simultaneous users
10 second response time [Average|Maximum|90th
percentile] response time
must be X seconds
Must handle 1M hits per
day
Must handle peak load
of 28 page requests per
second](https://image.slidesharecdn.com/10-140315000450-phpapp01/85/Software-Project-Management-lecture-10-42-320.jpg)
Software Project Management lecture 10
- 1. 1 Software Project Management Session 10: Integration & Testing
- 2. 2 Today • Software Quality Assurance • Integration • Test planning • Types of testing • Test metrics • Test tools • More MS-Project how-to
- 3. 3 Session 9 Review • Project Control – Planning – Measuring – Evaluating – Acting • MS Project
- 4. 4 Earned Value Analysis • BCWS • BCWP • Earned value • ACWP • Variances • CV, SV • Ratios • SPI, CPI. CR • Benefits – Consistency, forecasting, early warning
- 6. 6 Deliverables by Phase Software Concept Requirements Analysis Design Coding and Debugging Systems Testing Deployment & Maintenance Possible Deliverables by Phase Concept Document Statement of Work (SOW) Project Charter RFP & Proposal Requirements Document (Software Requirements Specification) Work Breakdown Structure (WBS) Functional Specification ( Top Level Design Specification) Entity Relationship Diagram Data Flow Diagram Detailed Design Specification Object Diagrams Detailed Data Model Coding Standards Working Code Unit Tests Acceptance Test Procedures Tested Application Maintenance Specification Deployed Application Project Development Plan (Software Development Plan ) Baseline Project Plan Quality Assurance Plan Configuration Management Plan Risk Management Plan Integration Plan Detailed SQA Test Plan SQA Test Cases User Documentation Training Plan
- 7. 7 If 99.9% Were Good Enough • 9,703 checks would be deducted from the wrong bank accounts each hour • 27,800 pieces of mail would be lost per hour • 3,000,000 incorrect drug prescriptions per year • 8,605 commercial aircraft takeoffs would annually result in crashes Futrell, Shafer, Shafer, “Quality Software Project Management”, 2002
- 8. 8 Development Costs 7% 16% 24% 24% 29% Requirements Preliminary Design Detailed Design Code & Unit Test Integration & System Test
- 9. 9 Integration & Testing • Development/Integration/Testing • Most common place for schedule & activity overlap • Sometimes Integration/Testing thought of as one phase • Progressively aggregates functionality • QA team works in parallel with dev. team
- 10. 10 Integration Approaches • Top Down • Core or overarching system(s) implemented 1st • Combined into minimal “shell” system • “Stubs” are used to fill-out incomplete sections – Eventually replaced by actual modules • Bottom Up • Starts with individual modules and builds-up • Individual units (after unit testing) are combined into sub-systems • Sub-systems are combined into the whole
- 11. 11 Integration • Who does integration testing? – Can be either development and/or QA team • Staffing and budget are at peak • “Crunch mode” • Issues • Pressure • Delivery date nears • Unexpected failures (bugs) • Motivation issues • User acceptance conflicts
- 12. 12 Validation and Verification • V & V • Validation – Are we building the right product? • Verification – Are we building the product right? – Testing – Inspection – Static analysis
- 13. 13 Quality Assurance • QA or SQA (Software Quality Assurance) • Good QA comes from good process • When does SQA begin? – During requirements • A CMM Level 2 function • QA is your best window into the project
- 14. 14 Test Plans (SQAP) • Software Quality Assurance Plan – Should be complete near end of requirements • See example – Even use the IEEE 730 standard
- 15. 15 SQAP • Standard sections – Purpose – Reference documents – Management – Documentation – Standards, practices, conventions, metrics • Quality measures • Testing practices
- 16. 16 SQAP • Standard sections continued – Reviews and Audits • Process and specific reviews – Requirements Review (SRR) – Test Plan Review – Code reviews – Post-mortem review – Risk Management • Tie-in QA to overall risk mgmt. Plan – Problem Reporting and Corrective Action – Tools, Techniques, Methodologies – Records Collection and Retention
- 17. 17 Software Quality • Traceability • Ability to track relationship between work products • Ex: how well do requirements/design/test cases match • Formal Reviews • Conducted at the end of each lifecycle phase • SRR, CDR, etc.
- 18. 18 Testing • Exercising computer program with predetermined inputs • Comparing the actual results against the expected results • Testing is a form of sampling • Cannot absolutely prove absence of defects • All software has bugs. Period. • Testing is not debugging.
- 19. 19 Test Cases • Key elements of a test plan • May include scripts, data, checklists • May map to a Requirements Coverage Matrix • A traceability tool
- 20. 20 Rework • Software equivalent of “scrap” in manufacturing 6% 1% 12% 4% 16% 8% 12% 12% 10% 19% 0% 5% 10% 15% 20% 25% 30% Requirements Detailed Design Integration & System Test Rew ork Production
- 22. 22 V Process Model Product Requirements and Specification Analysis Project Requirements and Planning Production, Operations, and Maintenance System Testing and Acceptance Testing Integration and Testing Unit Testing Coding Detailed Design High-Level Desig Non-functional Requirements Load & Performance Test User Interface Design Usability Test
- 23. 23 Project Testing Flow • Unit Testing • Integration Testing • System Testing • User Acceptance Testing
- 24. 24 Black-Box Testing • Functional Testing • Program is a “black-box” – Not concerned with how it works but what it does – Focus on inputs & outputs • Test cases are based on SRS (specs)
- 25. 25 White-Box Testing • Accounts for the structure of the program • Coverage – Statements executed – Paths followed through the code
- 26. 26 Unit Testing • a.k.a. Module Testing • Type of white-box testing – Sometimes treated black-box • Who does Unit Testing? • Developers • Unit tests are written in code – Same language as the module – a.k.a. “Test drivers” • When do Unit Testing? • Ongoing during development • As individual modules are completed
- 27. 27 Unit Testing • Individual tests can be grouped – “Test Suites” • JUnit • Part of the XP methodology • “Test-first programming”
- 28. 28 Integration Testing • Testing interfaces between components • First step after Unit Testing • Components may work alone but fail when put together • Defect may exist in one module but manifest in another • Black-box tests
- 29. 29 System Testing • Testing the complete system • A type of black-box testing
- 30. 30 User Acceptance Testing • Last milestone in testing phase • Ultimate customer test & sign-off • Sometimes synonymous with beta tests • Customer is satisfied software meets their requirements • Based on “Acceptance Criteria” – Conditions the software must meet for customer to accept the system – Ideally defined before contract is signed – Use quantifiable, measurable conditions
- 31. 31 Regression Testing – Re-running of tests after fixes or changes are made to software or the environment – EX: QA finds defect, developer fixes, QA runs regression test to verify – Automated tools very helpful for this
- 32. 32 Compatibility Testing – Testing against other “platforms” • Ex: Testing against multiple browsers • Does it work under Netscape/IE, Windows/Mac
- 33. 33 External Testing Milestones • Alpha 1st , Beta 2nd • Testing by users outside the organization • Typically done by users • Alpha release • Given to very limited user set • Product is not feature-complete • During later portions of test phase • Beta release • Customer testing and evaluation • Most important feature • Preferably after software stabilizes
- 34. 34 External Testing Milestones • Value of Beta Testing • Testing in the real world • Getting a software assessment • Marketing • Augmenting you staff • Do not determine features based on it • Too late! • Beta testers must be “recruited” • From: Existing base, marketing, tech support, site • Requires the role of “Beta Manager” • All this must be scheduled by PM
- 35. 35 External Testing Milestones • Release Candidate (RC) • To be sent to manufacturing if testing successful • Release to Manufacturing (RTM) • Production release formally sent to manufacturing • Aim for a “stabilization period” before each of these milestones • Team focus on quality, integration, stability
- 36. 36 Test Scripts • Two meanings • 1. Set of step-by-step instructions intended to lead test personnel through tests – List of all actions and expected responses • 2. Automated test script (program)
- 37. 37 Static Testing • Reviews • Most artifacts can be reviewed • Proposal, contract, schedule, requirements, code, data model, test plans – Peer Reviews • Methodical examination of software work products by peers to identify defects and necessary changes • Goal: remove defects early and efficiently • Planned by PM, performed in meetings, documented • CMM Level 3 activity
- 38. 38 Automated Testing • Human testers = inefficient • Pros • Lowers overall cost of testing • Tools can run unattended • Tools run through ‘suites’ faster than people • Great for regression and compatibility tests • Tests create a body of knowledge • Can reduce QA staff size • Cons • But not everything can be automated • Learning curve or expertise in tools • Cost of high-end tools $5-80K (low-end are still cheap)
- 39. 39 Test Tools • Capture & Playback • Coverage Analysis • Performance Testing • Test Case Management
- 40. 40 Load & Stress Testing • Push system beyond capacity limits • Often done via automated scripts • By the QA team • Near end of functional tests • Can show – Hidden functional issues – Maximum system capacity – Unacceptable data or service loss – Determine if “Performance Requirements” met • Remember, these are part of “non-functional” requirements
- 41. 41 Load & Stress Testing • Metrics – Minimal acceptable response time – Minimal acceptable number of concurrent users – Minimal acceptable downtime • Vendors: High-End – Segue – Mercury – Empirix
- 42. 42 Performance Metrics Source: Athens Consulting Group Bad Good Must support 500 users Must support 500 simultaneous users 10 second response time [Average|Maximum|90th percentile] response time must be X seconds Must handle 1M hits per day Must handle peak load of 28 page requests per second
- 43. 43 Other Testing • Installation Testing – Very important if not a Web-based system – Can lead to high support costs and customer dissatisfaction • Usability Testing – Verification of user satisfaction • Navigability • User-friendliness • Ability to accomplish primary tasks
- 44. 44 Miscellaneous • Pareto Analysis – The 80-20 rule • 80% of defects from 20% of code – Identifying the problem modules • Phase Containment – Testing at the end of each phase – Prevent problems moving phase-to-phase • Burn-in – Allowing system to run “longer” period of time – Variation of stress testing
- 45. 45 Miscellaneous • “Code Freeze” – When developers stop writing new code and only do bug fixes – Occurs at a varying point in integration/testing • Tester-to-Coder Ratio – It depends – Often 1:3 or 1:4 – QA staff size grows: QA Mgr and/or lead early
- 46. 46 Stopping Testing • When do you stop? • Rarely are all defects “closed” by release • Shoot for all Critical/High/Medium defects • Often, occurs when time runs out • Final Sign-off (see also UAT) • By: customers, engineering, product mgmt.,
- 47. 47 Test Metrics • Load: Max. acceptable response time, min. # of simultaneous users • Disaster: Max. allowable downtime • Compatibility: Min/Max. browsers & OS’s supported • Usability: Min. approval rating from focus groups • Functional: Requirements coverage; 100% pass rate for automated test suites
- 48. 48 Defect Metrics • These are very important to the PM • Number of outstanding defects – Ranked by severity • Critical, High, Medium, Low • Showstoppers • Opened vs. closed
- 49. 49 Defect Tracking • Get tools to do this for you – Bugzilla, TestTrack Pro, Rational ClearCase – Some good ones are free or low-cost • Make sure all necessary team members have access (meaning nearly all) • Have regular ‘defect review meetings’ – Can be weekly early in test, daily in crunch • Who can enter defects into the tracking system? – Lots of people: QA staff, developers, analysts, managers, (sometimes) users, PM
- 50. 50 Defect Tracking • Fields – State: open, closed, pending – Date created, updated, closed – Description of problem – Release/version number – Person submitting – Priority: low, medium, high, critical – Comments: by QA, developer, other
- 51. 51 Defect Metrics • Open Rates – How many new bugs over a period of time • Close Rates – How many closed over that same period – Ex: 10 bugs/day • Change Rate – Number of times the same issue updated • Fix Failed Counts – Fixes that didn’t really fix (still open) – One measure of “vibration” in project
- 52. 52 Defect Rates • Microsoft Study – 10-20/KLOC during test – 0.5/KLOC after release
- 53. 53 Test Environments • You need to test somewhere. Where? • Typically separate hardware/network environment(s)
- 54. 54 Hardware Environments • Development • QA • Staging (optional) • Production
- 55. 55 Hardware Environments • Typical environments – Development • Where programmers work • Unit tests happen here – Test • For integration, system, and regression testing – Stage • For burn-in and load testing – Production • Final deployment environment(s)
- 56. 56 Web Site Testing • Unique factors – Distributed (N-tiers, can be many) – Very high availability needs – Uses public network (Internet) – Large number of platforms (browsers + OS) • 5 causes of most site failures (Jupiter, 1999) – Internal network performance – External network performance – Hardware performance – Unforeseeable traffic spikes – Web application performance
- 57. 57 Web Site Testing • Commercial Tools: Load Test & Site Management – Mercury Interactive • SiteScope, SiteSeer – Segue • Commercial Subscription Services – Keynote Systems • Monitoring Tools • Availability: More “Nines” = More $’s • Must balance QA & availability costs vs. benefits
- 58. 58 QA Roles • QA Manager • Hires QA team; creates test plans; selects tools; manages team • Salary: $50-80K/yr, $50-100/hr • Test Developer/Test Engineer • Performs functional tests; develops automated scripts • Salary: $35-70K/yr, $40-100/hr • System Administrator • Supports QA functions but not official QA team member • Copy Editor/Documentation Writer • Supports QA; also not part of official team
- 60. 60 Homework • McConnell: 16 “Project Recovery” • Schwalbe: 16 “Closing” • Your final MS-Project schedule due class after next – Add resources and dependencies to your plan – Add durations and costs – Send interim versions – Remember, most important part of your grade – Get to me with any questions • Iterate & get feedback • Don’t work in the dark
- 61. 61 Questions?
Editor's Notes
- #3: No lab today More lab in later term