Table Of Content

1 Operating System Concepts 2 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Syllabus � 上課時間: Friday 19:35-22:00 � 教室:M 501 � 教科書： Silberschatz, Galvin, and Gagne, “Operating System Concept,” Seventh Edition, John Wiley & Sons, Inc., 2006. � 成績評量：(subject to changes.): 期中考(30%), 期末考(30%), 課堂參與(40%) 3 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Contents 1. Introduction 2. Computer-System Structures 3. Operating-System Structures 4. Processes 5. Threads 6. CPU Scheduling 7. Process Synchronization 8. Deadlocks 9. Memory Management 10.Virtual Memory 11.File Systems 4 Chapter 1. Introduction 5 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Introduction � What is an Operating System? � A basis for application programs � An intermediary between users and hardware � Amazing variety � Mainframe, personal computer (PC), handheld computer, embedded computer without any user view Convenient vs Efficient 6 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Computer System Components � OS – a government/environment provider Application Programs Operating System Hardware User User User ................. CPU, I/O devices, memory, etc. compilers, word processors, spreadsheets, browsers, etc. 7 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. User View � The user view of the computer varies by the interface being used! � Examples: � Personal Computer � Ease of use � Mainframe or minicomputer � maximization of resource utilization � Efficiency and fair share � Workstations � compromise between individual usability & resource utilization � Handheld computer � individual usability � Embedded computer without user view � run without user intervention 8 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. System View � A Resource Allocator � CPU time, Memory Space, File Storage, I/O Devices, Shared Code, Data Structures, and more � A Control Program � Control execution of user programs � Prevent errors and misuse � OS definitions – US Dept.of Justice against Microsoft in 1998 � The stuff shipped by vendors as an OS � Run at all time 9 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. System Goals � Two Conflicting Goals: � Convenient for the user! � Efficient operation of the computer system! � We should � recognize the influences of operating systems and computer architecture on each other � and learn why and how OS’s are by tracing their evolution and predicting what they will become! 10 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. UNIX Architecture terminal controller, terminals, physical memory, device controller, devices such as disks, memory, etc. CPU scheduling, signal handling, virtual memory, paging, swapping, file system, disk drivers, caching/buffering, etc. Shells, compilers, X, application programs, etc. UNIX Kernel interface to the hardware System call interface useruser user useruser user user User interface 11 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Mainframe Systems � The first used to tackle many commercial and scientific applications! � 0th Generation – 1940?s � A significant amount of set-up time in the running of a job � Programmer = operator � Programmed in binary � assembler � (1950) high level languages 12 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Mainframe – Batch Systems � Batches sorted and submitted by the operator � Simple batch systems � Off-line processing ~ Replace slow input devices with faster units � replace card readers with disks � Resident monitor ~ Automatically transfer control from one job to the next • loader • job sequencing • control card interpreter User Program Area monitor 13 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Mainframe – Batch Systems � Spooling (Simultaneous Peripheral Operation On- Line) ~ Replace sequential-access devices with random-access device => Overlap the I/O of one job with the computation of others e.g. card � disk, CPU services, disk � printer � Job Scheduling card reader disks CPU disks printer 14 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Mainframe – Multiprogrammed Systems � Multiprogramming increases CPU utilization by organizing jobs so that the CPU always has one to execute – Early 1960 � Multiporgrammed batched systems � Job scheduling and CPU scheduling � Goal : efficient use of scare resources disk monitor CPU scheduling job1 job2 job3 15 * All rights reserved, Tei-Wei Kuo, National Taiwan University, 2004. Mainframe – Time-Sharing Systems � Time sharing (or multitasking) is a logical extension of multiprogramming! � Started in 1960s and become common in 1970s. � An interactive (or hand- on) computer system � Multics, IBM OS/360 disk on-line file system virtual memory sophisticated CPU scheduling job synchronization protection & security ...... and so on