計(jì)算機(jī)操作系統(tǒng)OperatingSystemOverviewPPT課件

1、Contents第1頁/共52頁1.1 Objectives and Functions (p45)第2頁/共52頁1.1.1 Overview第3頁/共52頁1.1.2 OS as a User/Computer Interface (I)Figure 2.1 Layers and Views of a Computer SystemComputer HardwareOperating SystemUtilities (Compiler, Database)Applications ProgramsOperatingSystem DesignerProgrammersEnd User第4頁/

2、共52頁OS as a User/Computer Interface (II)第5頁/共52頁Services of the Operating System (I)第6頁/共52頁Services of the Operating System (II)第7頁/共52頁1.1.3 OS as Resource Manager (I)（p47）第8頁/共52頁OS as Resource Manager (II)第9頁/共52頁OS as Resource Manager (III Figure 2.2)第10頁/共52頁1.1.4 Ease of Evolution（p49）第11頁/共5

3、2頁1.2 The Evolution of Operating Systems第12頁/共52頁1.2.1 Serial Processing(p50串行處理串行處理)第13頁/共52頁1.2.2 Simple Batch System第14頁/共52頁From the Point of View of the Monitor (p51)Interrupt processingDevice DriversJob SequencingControl Language InterpreterUser Program AreamonitorMemory layout for a resident(

4、駐留) monitor第15頁/共52頁From the Point of View of the Processor第16頁/共52頁JCL (Job Control Language)第17頁/共52頁Other Hardware Feature Desirable(p53)第18頁/共52頁1.2.3 Multiprogrammed Batch SystemsRead one record0.0015 secondsExecute 100 instructions0.0001 secondsWrite one record0.0015 secondsTOTAL0.0031 seconds

5、Percent CPU Utilization = 0.0001/0.0031=3.2%Figure 2.4 System Utilization Example第19頁/共52頁Multiprogramming/Multitasking第20頁/共52頁Example of Multiprogramming 256k available memoryJOB1JOB2JOB3Type of JOBHeavy ComputerHeavy I/OHeavy I/ODuration5min15min10minMemory required50k100k80kNeed diskNoNoYesNeed

6、terminalNoYesNoNeed printerNoNoYesTable 2.1 Sample Program Execution Attributes 第21頁/共52頁Analysis第22頁/共52頁Analysis Single Processor use5/(5+15+10)=17% Memory use=(50*5+100*15+80*10)/256/30 =33% Disk use=10/30=33% Printer use10/30=33% Total time 5+15+1030 Throughput 6 job/hour Mean response time（5+20

7、+30）/3=18第23頁/共52頁Analysis Processor use5/15=33% Memory use=(50+100+80)*5+(100+80)*5+100*5/256/15 =65% Disk use=10/15=67% Printer use10/15=67% Total time15 Throughout 12job/hour Mean response time（5+10+15）/3=10第24頁/共52頁Sophisticated(復(fù)雜性復(fù)雜性) of Multiprogramming (p57)第25頁/共52頁1.2.4 Time-Sharing System

8、s第26頁/共52頁Batch Multiprogramming vs Timer SharingBatch Multiprogramming Time Sharing 第27頁/共52頁Reducing the Swapping Loads by Partial Swapping（p59）Reducing the spending for accessing disk 第28頁/共52頁1.3 Major Achievements（p60）第29頁/共52頁1.3.1 Processes第30頁/共52頁Errors May Happen in Multiprogramming第31頁/共5

9、2頁 Process entity(實(shí)體實(shí)體)第32頁/共52頁P(yáng)rocess Image and Process Switch（切換）（切換）(p63)第33頁/共52頁1.3.2 Memory Management第34頁/共52頁Fig 2.10 Two Views of a Storage SystemVirtual ProcessorReal ProcessorMapper (AddressTranslate)Main MemoryAuxiliaryMemoryVirtualMemoryFiles(a) Users View(b) Operating System Designers

10、 ViewVirtualAddressMemoryAddressSwappingRead, WriteCopyLong-term Store第35頁/共52頁1.3.3 Information Protection and Security第36頁/共52頁1.3.4 Scheduling and Resource Management（p66）第37頁/共52頁Some Concepts（p67）第38頁/共52頁Fig 2.11 Key elements of an Operating System for MultiprogrammingService CallHandlerInterr

11、uptHandlerLong-term QueueShort-term QueueShort-Term SchedulerI/O queueOS第39頁/共52頁System Structure(p68系統(tǒng)結(jié)構(gòu)系統(tǒng)結(jié)構(gòu))第40頁/共52頁Hierarchy (Table 2.4)第41頁/共52頁Hierarchy 第42頁/共52頁Hierarchy (Hardware) 第43頁/共52頁1.4 Characteristics of Modern OS (p71)第44頁/共52頁1.4.1 Microkernel 第45頁/共52頁1.4.2 Multithreading第46頁/共52頁1.4.3 Symmetric Multiprocessing (SMP p73