《实战整合营销学》完整讲稿Title

ComputerOperatingSystemsFANGDingyi(DepartmentofNetworking&CommunicationEng.TEL:88308273(lab);88308114(O)Email:销售信

1WordsbeforetheCourse:Textbook:OperatingSystems—InternalsandDesignPrinciples

(3irdor4thedition)，WilliamStalling,PrenticeHall/清华大学出版社;魏迎梅等译，电子工业出版社出版2WordsbeforetheCourse:Grade:30%(10%presentation+10%homewwork+10%project)+

30%(midtermexam)+40%(finalexam)Claimoftheexam:allquestionareinEnglish3WordsbeforetheCourse:Referenceboobs（inChinese）:1.《计算机操作系统》,骆斌等著，高等教育出版社；2.《计算机操作系统》,孙雅如、房鼎益著，西电出版社；

3.《计算机操作系统》,汤子赢等著，西电出版社；4.《计算机操作系统》,何炎祥等著，清华大学出版社；4ComputerSystemOverviewChapter15OperatingSystemExploitsthehardwareresourcesofoneormoreprocessors(充分利用处理机资源)Providesasetofservicestosystemusers(提供方便用户使用的服务)ManagessecondarymemoryandI/Odevices(管理外存与外设)BasicElementsProcessorMainMemoryreferredtoasrealmemoryorprimarymemoryVolatile(易挥发的—掉电后内容丢失)I/OmodulessecondarymemorydevicescommunicationsequipmentterminalsSystembuscommunicationamongprocessors,memory,andI/OmodulesTop-LevelComponentsProcessorRegistersUser-visibleregistersEnableprogrammertominimizemain-memoryreferencesbyoptimizingregisteruseControlandstatusregistersUsedbyprocessortocontroloperatingoftheprocessorUsedbyoperating-systemroutinestocontroltheexecutionofprogramsUser-VisibleRegistersMaybereferencedbymachinelanguageAvailabletoallprograms-applicationprogramsandsystemprogramsTypesofregistersDataAddressIndexSegmentpointerStackpointerUser-VisibleRegistersAddressRegistersIndexinvolvesaddinganindextoabasevaluetogetanaddressSegmentpointerwhenmemoryisdividedintosegments,memoryisreferencedbyasegmentandanoffsetStackpointerpointstotopofstackControlandStatusRegistersProgramCounter(PC)ContainstheaddressofaninstructiontobefetchedInstructionRegister(IR)ContainstheinstructionmostrecentlyfetchedProgramStatusWord(PSW)conditioncodesInterruptenable/disableSupervisor/usermodeControlandStatusRegistersConditionCodesorFlagsBitssetbytheprocessorhardwareasaresultofoperationsCanbe

accessedbyaprogrambutnotalteredExamplespositiveresultnegativeresultzeroOverflowInstructionExecutionTwostepsProcessorreadsinstructionsfrommemoryFetchesProcessorexecuteseachinstructionInstructionCycleInstructionFetchandExecuteTheprocessorfetchestheinstructionfrommemoryProgramcounter(PC)holdsaddressoftheinstructiontobefetchednextProgramcounterisincrementedaftereachfetchInstructionRegisterFetchedinstructionisplacedintheinstructionregisterTypesofinstructionsProcessor-memorytransferdatabetweenprocessorandmemoryProcessor-I/OdatatransferredtoorfromaperipheraldeviceDataprocessingarithmeticorlogicoperationondataControlaltersequenceofexecutionCharacteristicsofaHypotheticalMachineExampleofProgramExecutionDirectMemoryAccess(DMA)I/OexchangesoccurdirectlywithmemoryProcessorgrantsI/OmoduleauthoritytoreadfromorwritetomemoryRelievestheprocessorresponsibilityfortheexchangeProcessorisfreetodootherthingsInterruptsAninterruptionofthenormalsequenceofexecutionImprovesprocessingefficiencyAllowstheprocessortoexecuteotherinstructionswhileanI/OoperationisinprogressAsuspensionofaprocesscausedbyaneventexternaltothatprocessandperformedinsuchawaythattheprocesscanberesumedClassesofInterruptsProgramFlowofControlWithoutInterruptsProgramFlowofControlWithInterrupts,ShortI/OWaitProgramFlowofControlWithInterrupts;LongI/OWaitInterruptHandlerAprogramthatdeterminesnatureoftheinterruptandperformswhateveractionsareneededControlistransferredtothisprogramGenerallypartoftheoperatingsystemInterruptsSuspendsthenormalsequenceofexecutionInterruptCycleInterruptCycleProcessorchecksforinterruptsIfnointerruptsfetchthenextinstructionforthecurrentprogramIfaninterruptispending(待解决的),suspendexecutionofthecurrentprogram,andexecutetheinterrupt-handlerroutineTimingDiagramBasedonShortI/OWaitTimingDiagramBasedonShortI/OWaitSimpleInterruptProcessingChangesinMemoryandRegistersforanInterruptChangesinMemoryandRegistersforanInterruptMultipleInterruptsDisableinterruptswhileaninterruptisbeingprocessedMultipleInterruptsDefineprioritiesforinterruptsMultipleInterruptsMultiprogrammingProcessorhasmorethanoneprogramtoexecuteThesequencetheprogramsareexecuteddependontheirrelativepriorityandwhethertheyarewaitingforI/OAfteraninterrupthandlercompletes,controlmaynotreturntotheprogramthatwasexecutingatthetimeoftheinterruptMemoryHierarchyFasteraccesstime,greatercostperbitGreatercapacity,smallercostperbitGreatercapacity,sloweraccessspeedMemoryHierarchyGoingDowntheHierarchyDecreasingcostperbitIncreasingcapacityIncreasingaccesstimeDecreasingfrequencyofaccessofthememorybytheprocessorLocalityofreferenceSecondaryMemoryNonvolatileAuxiliarymemoryUsedtostoreprogramanddatafilesDiskCacheAportionofmainmemoryusedasabuffertotemporarilytoholddataforthediskDiskwritesareclusteredSomedatawrittenoutmaybereferencedagain.ThedataareretrievedrapidlyfromthesoftwarecacheinsteadofslowlyfromdiskCacheMemoryInvisibletooperatingsystemIncreasethespeedofmemoryProcessorspeedisfasterthanmemoryspeedExploittheprincipleoflocalityCacheMemoryCacheMemoryContainsacopyofaportionofmainmemoryProcessorfirstcheckscacheIfnotfoundincache,theblockofmemorycontainingtheneededinformationismovedtothecacheanddeliveredtotheprocessorCache/MainMemorySystemCacheReadOperationCacheDesignCachesizeSmallcacheshaveasignificantimpactonperformanceBlocksizeTheunitofdataexchangedbetweencacheandmainmemoryLargerblocksizemorehitsuntilprobabilityofusingnewlyfetcheddatabecomeslessthantheprobabilityofreusingdatathathavetobemovedoutofcacheCacheDesignMappingfunctionDetermineswhichcachelocationtheblockwilloccupyReplacementalgorithmDetermineswhichblocktoreplaceLeast-Recently-Used(LRU)algorithmCacheDesignWritepolicyWhenthememorywriteoperationtakesplaceCanoccureverytimeblockisupdatedCanoc