Process ImprovementObjectivesTopics coveredProcess improvementProcess attributesProcess improvement stagesThe process improvement processProcess and product qualityPrincipal product quality factorsQuality factorsProcess analysis and modellingSlide 12Process analysis techniquesElements of a process modelThe module testing activityActivities in module testingProcess exceptionsProcess measurementClasses of process measurementGoal-Question-Metric ParadigmThe Software Engineering InstituteThe SEI process maturity modelMaturity model levelsKey process areasSEI model problemsThe CMM and ISO 9000Capability assessmentThe capability assessment processProcess classificationProcess applicabilityProcess choiceProcess tool supportKey pointsSlide 34©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 1Process Improvement©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 2To explain the principles of software process improvementTo explain how software process factors influence software quality and productivityTo introduce the SEI Capability Maturity Model and to explain why it is influential. To discuss the applicability of that modelTo explain why CMM-based improvement is not universally applicableObjectives©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 3Process and product qualityProcess analysis and modellingProcess measurementThe SEI process maturity modelProcess classificationTopics covered©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 4Understanding existing processesIntroducing process changes to achieve organisational objectives which are usually focused on quality improvement, cost reduction and schedule accelerationMost process improvement work so far has focused on defect reduction. This reflects the increasing attention paid by industry to qualityHowever, other process attributes can be the focus of improvementProcess improvement©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 5Process attributes©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 6Process analysis•Model and analyse (quantitatively if possible) existing processesImprovement identification•Identify quality, cost or schedule bottlenecksProcess change introduction•Modify the process to remove identified bottlenecksProcess change training•Train staff involved in new process proposalsChange tuning•Evolve and improve process improvementsProcess improvement stages©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 7The process improvement processProcessmodelProcess changeplanTrainingplanFeedback onimprovementsRevised processmodelAnalyseprocessIdentifyimprovementsTuneprocess changesIntroduceprocess changeTrainengineers©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 8Process quality and product quality are closely relatedA good process is usually required to produce a good productFor manufactured goods, process is the principal quality determinantFor design-based activity, other factors are also involved especially the capabilities of the designersProcess and product quality©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 9Principal product quality factorsProductqualityDevelopmenttechnologyCost, time andscheduleProcessqualityPeoplequality©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 10Quality factorsFor large projects with ‘average’ capabilities, the development process determines product qualityFor small projects, the capabilities of the developers is the main determinantThe development technology is particularly significant for small projectsIn all cases, if an unrealistic schedule is imposed then product quality will suffer©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 11Process analysis and modellingProcess analysis•The study of existing processes to understand the relationships between parts of the process and to compare them with other processesProcess modelling•The documentation of a process which records the tasks, the roles and the entities used•Process models may be presented from different perspectives©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 12Study an existing process to understand its activitiesProduce an abstract model of the process. You should normally represent this graphically. Several different views (e.g. activities, deliverables, etc.) may be requiredAnalyse the model to discover process problems. Involves discussing activities with stakeholdersProcess analysis and modelling©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 13Published process models and process standards•It is always best to start process analysis with an existing model. People then may extend and change this.Questionnaires and interviews•Must be carefully designed. Participants may tell you what they think you want to hearEthnographic analysis•Involves assimilating process knowledge by observationProcess analysis techniquesElements of a process model©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 15The module testing activityTestmoduleSigned-off testrecordModule testdataModulespecificationModule compileswithout syntaxerrorsAll defined testsrun on moduleTestengineerPre-conditionInputProcessRôlePost-conditionOutputsResponsibleforActivities in module testingPrepare test da taaccor ding tospecificationRead modulespecificationSubmit test datafor reviewReview test dataTEST DATA PREPARATIONRead and understandmodule interfaceCheckout modulefrom configurationmana gement systemPrepare test harnessfor moduleCompile testharnessMODULE TEST HARNESS PREPARATIONIncorporate modulewith test harnessRun approved testson moduleRecord test resultsfor regression testsTEST EXECUTIONWrite report on moduletesting including detailsof discovered problemsSubmit reportfor approvalSubmit testresults to CMTEST REPORTING©Ian Sommerville 1995 Software Engineering, 5th edition. Chapter 31. Slide ##©Ian Sommerville 2004 Software Engineering, 7th edition. Chapter 28 Slide 17Process exceptionsSoftware processes are