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Oct 30, 2014





  • 1. Operating Systems Tim Ji Lecture 1
    • Outline
    • Course Information
    • History of Operating Systems
    • Basic Components of OS
  • Lab 1
  • Become familiar with Linux
  • Readings
  • Chapter 1

2. 1 Course Information

  • Official Course Outline
    • On course webpage, MS Word document
  • Course Objectives/Learning Outcomes
    • Understand OS algorithms
    • Be able to write multitasking programs with a variety of inter-process communication methods
    • Be able to write scheduling, paging algorithms
  • Textbook: Tanenbaum, Modern Operating Systems 2 ndEdition, Prentice Hall

3. 4. Course Information (2)

  • Instructor
    • Name: Tim Ji
    • Email tji AT
    • Office: 2A503, x2230
    • Office hour: Drop by my office or by appointment
  • Grading
    • 3 tests, 20% each:60%
    • Assignments + Labs: 40%
  • Assignments
    • Due in class at the end of lecture, 20% reduction in the assignment mark for each school day it is late.
    • The assignments must be your own work. Cheating/copying other peoples files will result in both papers receiving zero.

5. Course Information (3)

  • Labs
    • Lab tasks will be demonstrated in the following week lab, and lab reports must be submitted by the end of the lab. You have 1 week to finish the lab task.
  • Course website
    • Announcements, assignments, lecture handouts, etc.
    • Check it out at least once per day.
  • Study to pass
    • You have to pass both the tests portion and the assignments portion
  • Assignments/Labs marking
    • Demonstrate your task in lab
    • Answer questions regarding to your own task
    • Programming style of printouts of your source code, for programming assignments/labs

6. Introduction to Operating Systems

  • Topics:
    • Role and purpose of the operating system
    • History of operating system development
    • Functionality of a typical operating system
  • Learning Objectives:
    • Explain the objectives and functions of modern operating systems.
    • Describe how operating systems have evolved over time from primitive batch systems to sophisticated multiuser systems.
    • Describe the functions of a contemporary operating system with respect to convenience, efficiency, and the ability to evolve.

7. Early Computers

  • First Computer
    • Charles Babbage (1791-1871) designed the first true digital computer called theanalytical engine .
    • That was purely mechanical and intended to do math operations
    • The engine was supposed to be made of brass, and steam powered
    • He did not actually built the machine but inspired others in the field.

8. Early Computers

  • Babbage also thought of the concept ofsoftware
  • And hired the first programmer (LadyAda , Countess of Lovelace) for his analytical engine

9. Current Computer Systems

  • A computer system consists of
    • hardware
    • system programs
    • application programs

10. What is an Operating System (1)

  • Microsoft Glossary:
    • Thesoftwarethat controls the allocation and usage of hardware resources such as memory, central processing unit (CPU) time, hard disk space, and peripheral devices (like speakers or a mouse).
    • The operating system is the foundationsoftwareon which programs, such as Word or Excel, depend.
    • An example of an operating system is Microsoft Windows XP.

11. What is an Operating System (2)

  • Provide a service for clients - a virtual machine (top-down view)
  • Anoperating systemis a layer of the computer system (a virtual machine) between the hardware and user programs.
    • Multiple processes
    • Multiple address spaces
    • File system

12. What is an Operating System (3)

  • Resource manager (bottom-up view)
  • Anoperating systemis aresource manager . Resource management includes
    • Transforming resources - to provide an easier to use version of a resource
    • Multiplexing resources - create the illusion of multiple resources
    • Scheduling resources - when and who gets a resource
  • The hardware resources it manages include
    • Processors - process management system
    • Memory - memory management system
    • I/O devices - I/O system
    • Disk space - file system

13. What is an Operating System (4)

  • The hardware resources are transformed into virtual resources so that an operating system may be viewed as providing avirtual computers , one to each user. Avirtual machine(top down view) consists of
    • Processes - virtualization of the computer including a virtual processor that abstracts the cpu - user mode instruction set + system calls
    • Virtual memory - virtualization of physical memory
    • Logical devices - virtualization of physical devices
    • Files - virtualization of disk space

14. What is an Operating System (5)

  • The general functions of an operating system
    • Allocation - assigns resources to processes needing the resource
    • Accounting - keeps track of resources - knows which are free and which process the others are allocated to.
    • Scheduling - decides which process should get the resource next.
    • Protection - makes sure that a process can only access a resource when it is allowed
  • Basic Functions
    • Process management
    • Resource management
      • Device managment
      • Memory management
      • File management

15. History of Operating Systems (1)

  • First generation 1945 - 1955
    • Technology:vacuum tubes & plugboards
    • Programming:setting some switches
    • Programming language:machine language
    • Tasks:tables of sine, cosine, logarithms
    • OS:none

16. A Famous Remark

  • "I think there is a world market for maybe five computers."
    • Thomas Watson, chairman of IBM - 1943

17. History of Operating Systems (2)

  • Second generation 1955 1965
    • Technology:Transistors
    • Programming:Punched cards
    • Programming languages:FORTRAN & Assembly
    • Tasks:Scientific
    • Computer:Mainframes
    • OS:Batch system
  • Universities started to buy computers (millions $)


    • bring cards to IBM 1401 machine (good at card reading)
    • read cards to tape
    • put tape on IBM 7094 which does computing
    • put tape on IBM 1401 which prints output offline

Early Batch System 19. Famous Remarks

  • "I have traveled the length and breadth of this country and talked with the best people, and I can assure you that data processing is a fad that won't last out the year.
    • The editor in charge of business books for Prentice Hall - 1957

20. History of Operating Systems (3)

  • Third generation 1965 1980
    • Technology:ICs
    • Programming:Punched card