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operating system

Contents 
CHAPTER 1: INTRODUCTION TO OPERATING SYSTEM ............................................................ 5 
Introduction to Operating system .............................................................................................................. 5 
Operating Systems Terminology’s ............................................................................................................ 6 
The History of Operating Systems ............................................................................................................ 7 
Operating System Structure ...................................................................................................................... 9 
Operating System ─ Types ...................................................................................................................... 11 
Operating System ─ Properties ............................................................................................................... 14 
Job control .............................................................................................................................................. 18 
CHAPTER 2: PROCESS MANAGEMENT .......................................................................................... 20 
Definition of a Process and terms ........................................................................................................... 20 
The Process Model .................................................................................................................................. 21 
Process Levels ..................................................................................................................................... 21 
Process States Life Cycle ..................................................................................................................... 28 
Inter-process communication ................................................................................................................. 30 
Race Conditions................................................................................................................................... 30 
Critical Section .................................................................................................................................... 31 
Mutual Exclusion ................................................................................................................................. 31 
Using Systems calls 'sleep' and 'wakeup' ............................................................................................ 33 
Semaphore & Monitor ........................................................................................................................ 34 
Process scheduling .................................................................................................................................. 36 
Definition ............................................................................................................................................ 36 
Process Scheduling Queues ................................................................................................................ 36 
Process scheduling and Job scheduling .............................................................................................. 38 
Schedulers ........................................................................................................................................... 39 
Context Switch .................................................................................................................................... 41 
Process Scheduling Algorithms ........................................................................................................... 42 
Deadlock ................................................................................................................................................. 45 
Introduction ........................................................................................................................................ 45 
Deadlock Characterization .................................................................................................................. 46 
Resource-Allocation Graph ................................................................................................................. 46 
Page 3 of 101 
 
 
Method for Handling Deadlock //Detection ....................................................................................... 48 
Description of Error Diagnosis ................................................................................................................ 52 
CHAPTER 3: MEMORY MANAGEMENT ......................................................................................... 54 
Introduction to Memory management ................................................................................................... 54 
Memory management Objective ........................................................................................................ 54 
Memory management Concepts ............................................................................................................ 54 
Static vs Dynamic Loading ................................................................................................................... 55 
Static vs Dynamic Linking .................................................................................................................... 56 
Memory allocation technique ................................................................................................................. 56 
Contiguous Allocation ......................................................................................................................... 58 
Paging .................................................................................................................................................. 59 
Virtual Memory ....................................................................................................................................... 62 
Basic Concept of virtual memory ........................................................................................................ 62 
Demand Paging ................................................................................................................................... 64 
Page Replacement Algorithm ............................................................................................................. 66 
Segmented paging and Paged segmentation?.................................................................................... 69 
CHAPTER 4: DEVICE (1/0) MANAGEMENT .................................................................................... 74 
Objectives of device (I/O) management ................................................................................................. 74 
Principles of device (I/O) Hardware ........................................................................................................ 75 
Device Controllers ............................................................................................................................... 76 
Direct Memory Access (DMA) ............................................................................................................. 78 
Principles of I/O Software ....................................................................................................................... 80 
Goals of the I/O Software ................................................................................................................... 80 
Introduction to I/O software ............................................................................................................... 81 
Device Drivers ..................................................................................................................................... 82 
Interrupt handlers ............................................................................................................................... 82 
Device-Independent I/O Software ...................................................................................................... 83 
User-Space I/O Software ..................................................................................................................... 83 
Kernel I/O Subsystem .......................................................................................................................... 83 
Disks and disk operations ....................................................................................................................... 84 
Overview of Mass-Storage Structure .................................................................................................. 84 
Page 4 of 101 
 
 
Disk Structure ...................................................................................................................................... 86 
Disk Performance Parameters ............................................................................................................ 86 
Disk Scheduling ................................................................................................................................... 87 
Disk Management ............................................................................................................................... 89 
Swap Space Management ................................................................................................................... 89 
Stable Storage Implementation .......................................................................................................... 90 
Disk Reliability ..................................................................................................................................... 90 
Summary ............................................................................................................................................. 90 
Computer clocking system ...................................................................................................................... 91 
Introduction to system clocking .......................................................................................................... 91 
The hardware and software clocks ..................................................................................................... 91 
Computer terminals ................................................................................................................................ 92 
Computer Terminal Hardware ............................................................................................................ 92 
Summary ............................................................................................................................................. 93 
Input/Output software ....................................................................................................................... 93 
Virtual devices ......................................................................................................................................... 93 
Objective of Virtual devices ................................................................................................................ 93 
History of Virtual devices .................................................................................................................... 93 
Virtual Device Types ............................................................................................................................ 94 
CHAPTER 5: FILE MANAGEMENT ................................................................................................... 96 
File management .................................................................................................................................... 96 
File system .............................................................................................................................................. 96 
File Concept......................................................................................................................................... 96 
File Structure ....................................................................................................................................... 96 
File Attributes ...................................................................................................................................... 97 
File Operations .................................................................................................................................... 97 
File Types – Name, Extension ............................................................................................................. 98 
File Management Systems: ..................................................................................................................... 98 
File-System Mounting ........................................................................................................................... 100 
File Access Mechanisms ........................................................................................................................ 100 
Space Allocation .................................................................................................................................... 100