Lecture Operating systems: A concept-based approach (2/e): Chapter 14 - Dhananjay M. Dhamdhere

PROPRIETARY MATERIAL. © 2007 The McGraw­Hill Companies, Inc. All rights reserved. No part of this PowerPoint slide may be displayed, reproduced or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw­Hill for their individual course preparation. If you are a student using this PowerPoint slide, you are using it without permission. Chapter 14: Structure of Operating Systems Dhamdhere: Operating Systems— A Concept­Based Approach, 2 ed Slide No: 1 Copyright © 2008 Functions performed by an OS • An OS performs the following functions – User interface – Process management – Memory management – I/O management – File management – Protection and Security • OS should be structured so that it can cope with changes in computer systems and computing environments Chapter 14: Structure of Operating Systems Dhamdhere: Operating Systems— A Concept­Based Approach, 2 ed Slide No: 2 Copyright © 2008 Operation of an OS • Three key aspects of OS operation are – Booting * Determines configuration of the system, viz. CPU, I/O devices, etc. * Loads the kernel, initializes its data structures and hands over control – Interrupt handling * Events are handled to perform resource allocation, I/O and initiation / termination of programs – Scheduling * A process is chosen for servicing Chapter 14: Structure of Operating Systems Dhamdhere: Operating Systems— A Concept­Based Approach, 2 ed Slide No: 3 Copyright © 2008 Interrupt handling • An event causes an interrupt, which passes control to the kernel • An appropriate interrupt handler is invoked to handle the event • The scheduler selects the process to be serviced next Chapter 14: Structure of Operating Systems Dhamdhere: Operating Systems— A Concept­Based Approach, 2 ed Slide No: 4 Copyright © 2008 A view of OS operation • The memory is divided into ‘system area’ and ‘user area’ • Some components of OS reside permanently in memory; others are loaded as needed Chapter 14: Structure of Operating Systems Dhamdhere: Operating Systems— A Concept­Based Approach, 2 ed Slide No: 5 Copyright © 2008 ... - tailieumienphi.vn