Lesson 6 Operating System Operating systems have developed over several decades for mainly two reasons. First, they allow computer users to develop and execute programs in a convenient environment. Secondly, operating systems do a lot of favor to ensure a good performance of the computing system. ...
operating sytem《操作系统》ch02-operating-system structures-42.ppt,Solaris Modular Approach Mac OS X hybrid structure 2.8 Virtual Machines The fundamental idea behind a virtual machine is to abstract the hardware of a single computer into several differe
Accounting - To keep track of which users use how much and what kinds of computer resources Protection and security - The owners of information stored in a multiuser or networked compute 10、r system may want to control use of that information, concurrent processes should not interfere with ...
waysinwhichthesystemresourcesareusedtosolvethecomputingproblemsoftheusers Wordprocessors,compilers,webbrowsers,databasesystems,videogames Users People,machines,othercomputers1.7Silberschatz,GalvinandGagne©2005OperatingSystemConcepts–7thEdition,Jan12,2005FourComponentsofaComputerSystemFourComponentsofaComputerSystem1.8...
SystemCalls(1/7)•SystemcallsprovideaninterfacetotheservicesmadeavailablebyanOS.•Inotherwords,systemcallsarethewayofoperatingthecomputerviatheOS.•Asanenduser,esp.thosewhoarefamiliarwithGUI,theinvokingofsystemcallsarehiddenfromapplicationsoftware.不同的机构都有各自的特点,把各种机构按结构加以分类,其目的...
2)CPU等待人工操作。1-2I/O 2.脱机输入/输出(Off-LineI/O)这种脱机I/O(1)减少了CPU的空闲时间。(2)提高I/O速度。输入设备图 脱机示意图 外围机主机外围机 磁盘输出设备 1.2.2单道批处理系统 1.单道批处理系统(SimpleBatchProcessingSystem：内存里仅有一道作业)的处理过程 开始 还有下一个作业？否 ...
Figure2.1LayersandViewsofaComputerSystem - 3 作業系統作為資源管理者 作業系統與一般電腦軟體一樣，都是由處理器執行的程式。作業系統常讓出控制權，並且需要重新取得控制權。核心(kernel,nucleus)：包含作業系統最常被使用的函式。Figure2.2TheOperatingSystemasResourceManager - 4 簡化作業系統的演進 作業系統會不...
SystemCalls(1/7)•SystemcallsprovideaninterfacetotheservicesmadeavailablebyanOS.•Inotherwords,systemcallsarethewayofoperatingthecomputerviatheOS.•Asanenduser,esp.thosewhoarefamiliarwithGUI,theinvokingofsystemcallsarehiddenfromapplicationsoftware.SystemCalls(2/7)•Systemcallsequencetocopythecontentsof...
4.2 Silberschatz, Galvin and Gagne ©2005 Operating System Concepts Threads A thread (or lightweight process) is a basic unit of CPU. PRINCIPLES OF OPERATING SYSTEMS Lecture 6: Processes CPSC 457, Spring 2015 May 21, 2015 M. Reza Zakerinasab Department of Computer Science, University. 10...
in a modern computer system Explain how protection domains combined with an access matrix are used to specify the resources a process may access Examine capability and language-based protection systems 14.3 Goals of Protection Operating system consists of a collection of objects, hardware or software ...