Lecture Operating system concepts (Sixth ed) - Chapter 1: Introduction. In this chapter, you will learn to: To describe the basic organization of computer systems, to provide a grand tour of the major components of operating systems, to give an overview of the many types of computing environments, to explore several open-source operating systems. | Chapter 1: Introduction I What is an Operating System? I Mainframe Systems I Desktop Systems I Multiprocessor Systems I Distributed Systems I Clustered System I Real -Time Systems I Handheld Systems I Computing Environments Operating System Concepts Silberschatz, Galvin and Gagne 2002 What is an Operating System? I A program that acts as an intermediary between a user of a computer and the computer hardware. I Operating system goals: ✦ Execute user programs and make solving user problems easier. ✦ Make the computer system convenient to use. I Use the computer hardware in an efficient manner. Operating System Concepts Silberschatz, Galvin and Gagne 2002 Computer System Components 1. Hardware – provides basic computing resources (CPU, memory, I/O devices). 2. Operating system – controls and coordinates the use of the hardware among the various application programs for the various users. 3. Applications programs – define the ways in which the system resources are used to solve the computing problems of the users (compilers, database systems, video games, business programs). 4. Users (people, machines, other computers). Operating System Concepts Silberschatz, Galvin and Gagne 2002 Abstract View of System Components Operating System Concepts Silberschatz, Galvin and Gagne 2002 Operating System Definitions I Resource allocator – manages and allocates resources. I Control program – controls the execution of user programs and operations of I/O devices . I Kernel – the one program running at all times (all else being application programs). Operating System Concepts Silberschatz, Galvin and Gagne 2002 Mainframe Systems I Reduce setup time by batching similar jobs I Automatic job sequencing – automatically transfers control from one job to another. First rudimentary operating system. I Resident monitor ✦ initial control in monitor ✦ control transfers to job ✦ when job completes control transfers pack to .
