topics computer & software operating system strategies learning outcomes: student able to...
TRANSCRIPT
CHAPTER 1: INTRODUCTION
TO OERATING SYSTEM• TOPICS
•Computer & Software• Operating System Strategies
Learning Outcomes:•Student able to identify key component in OS•Student able to know OS strategies
Learning Objectives:•Introduction to OS basic and fundamentals•The key element in OS•Environment in OS
Why studying OSTo extract the best performance from OSTo understand how to use the system functionality most effectiveTo understand and exploit design during program execution
Computer system & Software Computer System
Provide tool to solve specific problems
Application Software
HardwareSoftware
System Software
To solve specific problem
provide general programming environment to create
application needs.OS is subset of syst. sw
Differences between Syst. Software and Application SoftwareSystem Software Application Software
Supports the use in computer operations
Manages computer machine resources such as register,CPU, I/O syst
Written in Low level language. Eg: assembly language
Used as long as computer is turned on.
Performs more than one job or task related at a time(multitasking)
Control many processes at a time
Concern problem solving and the use of computer as a tools
Manages operation data such as insert, delete, update and sorting.
Written in high level language such as Pascal, C++,VB, Java
Use only when it’s needed
Performs only one job or task at a
Process done by following step by step at a time.
Function OS
Interface between hardware and user which is responsible for the management.
To coordinate of activities and the sharing of the resources of a computer, that acts as a host for computing.
Eg: Programmer use OS to implement application software
To handle the resource allocation an access protection of the hardware.
to provide maintain a platform for running application software
Example OS: MS Dos, Ms Windows, Mac OS, Linux and Unix
OS Strategies
Batch Processing Timesharing Personal Computers & workstation Process Control & real time
computers Network Technology
1. Batch Processing
Set of jobs is submitted in sequence for processing. These systems have a relatively long average turnaround period (interval from arrival time to completion) for jobs.
Services a collection of jobs called a batch Jobs: unit of work submitted by a user to the OS. A job usually consists of a program and the data
to be run. Jobs are stored in job queues until the computer
is ready to process them. There is no interaction between the user and the
computer while the program is being run. Computers which do batch processing often operate at night.
Only one program can be run during one cycle.(not multiuser program)
Example : Payroll - when a company calculates the wages for its workforce and prints payslips.
1. Batch Processing
2. Time Sharing
Support multiple user. Called as interactive system or conversation. Basic functions and facilities in a time sharing
system: a) Users can access main memory at the same
time. Time sharing system supposedly to keep each of the memory space for each users and provide equal time allocation for each processor
b) Processor has to be able do multitasking by having interuptablity.
Eg: mainframe and mini computers are time sharing systems.
3. Personal computers and workstations A workstation is a high-end
microcomputer higher performance than Personal
Computer (CPU and graphics, memory capacity and multitasking capability)
multi-user sharing of a single computer toward an environment.
These single-user machines are multiprogrammed so that the computer can be performing several different tasks concurrently on behalf of the user.
MINICOMPUTERFirst generation
Digital Equipment Corporation (DEC) PDP-8 on display at the
National Museum of American History
Inexpensive and easy to install in
any location.
MICROCOMPUTERThe Commodore 64 was one of the most popular microcomputers of its era, and is the best-selling model of home computer of all time.[1]
http://en.wikipedia.org/wiki/Microcomputer
4. Process control and real-time computers used to control “autonomous
systems” such as hydroelectric dams, satellites, and robots.
This multiprogramming OS is required to guarantee response time for particular computing tasks
Example: Automatics System, Airplane Computer System, Online Bank System
5. Network technology
Modern computer configurations use high-speed networks to interconnect groups of personal computers, workstations, batch system, timesharing systems, and sometimes even real-time systems.
Need for resources and information sharing across the network
references
Nutt Gary Operating System : A modern perspective , Addison Wesley.