Operating Systems

Course Description:

This course includes the basic concepts of operating system components. It consists of process management, deadlocks and process synchronization, memory management techniques, File system implementation, and I/O device management principles. It also includes case study on Linux operating system.

Course Objectives:

The main objective of this course is to describe need and role of operating system, understand OS components such a scheduler, memory manager, file system handlers and I/O device managers, analyze and criticize techniques used in OS components, demonstrate and simulate algorithms used in OS components, and identify algorithms and techniques used in different components of Linux.

Course Contents:

Unit 1: Operating System Overview (4 Hrs.)

Definition, Two views of operating system, Evolution of operating system, Types of OS; System Call, Handling System Calls, System Programs, Operating System Structures, The Shell, Open Source Operating Systems

Unit 2: Process Management (10 Hrs.)

Process vs Program, Multiprogramming, Process Model, Process States, Process Control Block; Threads, Thread vs Process, User and Kernel Space Threads; Inter Process Communication, Race Condition, Critical Section; Implementing Mutual Exclusion: Mutual Exclusion with Busy Waiting (Disabling Interrupts, Lock Variables, Strict Alteration, Peterson’s Solution, Test and Set Lock), Sleep and Wakeup, Semaphore, Monitors, Message Passing; Classical IPC problems: Producer Consumer, Sleeping Barber, Dining Philosopher Problem; Process Scheduling: Goals, Batch System Scheduling (First-Come First-Served, Shortest Job First, Shortest Remaining Time Next), Interactive System Scheduling (Round-Robin Scheduling, Priority Scheduling, Multiple Queues), Overview of Real Time System Scheduling

Unit 3: Process Deadlocks (6 Hrs.)

Introduction, Deadlock Characterization, Preemptable and Non-preemptable Resources, Resource – Allocation Graph, Conditions for Deadlock; Handling Deadlocks: Ostrich Algorithm, Deadlock prevention, Deadlock Avoidance, Deadlock Detection (For Single and Multiple Resource Instances), Recovery From Deadlock (Through Preemption and Rollback)

Unit 4: Memory Management (8 Hrs.)

Introduction, Monoprogramming vs. Multi-programming, Modelling Multiprogramming, Multiprogramming with fixed and variable partitions, Relocation and Protection; Memory management (Bitmaps & Linked-list), Memory Allocation Strategies; Virtual memory: Paging, Page Table, Page Table Structure, Handling Page Faults, TLB’s; Page Replacement Algorithms: FIFO, Second Chance, LRU, Optimal, LFU, Clock, WSClock, Concept of Locality of Reference, Belady’s Anomaly; Segmentation: Need of Segmentation, its Drawbacks, Segmentation with Paging (MULTICS)

Unit 5: File Management (6 Hrs.)

File Overview: File Naming, File Structure, File Types, File Access, File Attributes, File Operations, Single Level, two Level and Hierarchical Directory Systems, File System Layout; Implementing Files: Contiguous allocation, Linked List Allocation, Linked List Allocation using Table in Memory, Inodes; Directory Operations, Path Names, Directory Implementation, Shared Files; Free Space Management: Bitmaps, Linked List

Unit 6: Device Management (6 Hrs.)

Classification of IO devices, Controllers, Memory Mapped IO, DMA Operation, Interrupts; Goals of IO Software, Handling IO (Programmed IO, Interrupt Driven IO, IO using DMA), IO Software Layers (Interrupt Handlers, Device Drivers); Disk Structure, Disk Scheduling (FCFS, SSTF, SCAN, CSCAN, LOOK, CLOOK), Disk Formatting (Cylinder Skew, Interleaving, Error handling), RAID

Unit 7: Linux Case Study (5 Hrs.)

History, Kernel Modules, Process Management, Scheduling, Inter-process Communication, Memory Management, File System Management Approaches, Device Management Approaches.

Laboratory Works:

The laboratory work includes solving problems in operating system. The lab work should include at least; Learn basic Linux Commands; Create process, threads and implement IPC techniques; Simulate process Scheduling algorithms and deadlock detection algorithms; Simulate page replacement algorithms; Simulate free space management techniques and disk scheduling algorithms.

Text Books:

1. Modern Operating Systems, Andrew S. Tanenbaum, 3^rd Edition, PH1 Publication, 2008

Reference Books:

1. Abraham Silberschatz, Peter Baer Galvin and Greg Gagne, Operating System Concepts, 7^th Edition, John Wiley & Sons (ASIA) Pvt. Ltd, 2005
2. Harvey M. Deitel, Paul J. Deitel, and David R. Choffnes, Operating Systems, 3^rd Edition, Prentice Hall, 2003