Week 2:

 

Week 2: Process Management and Shell Scripting

• Topics:
  • Processes and process states
  • Process control block (PCB)
  • Context switching
  • Basic shell scripting
• Activities:
  • Lab: Writing simple shell scripts
  • Discussion forum: The role of processes in an OS
  • Quiz: Process Managemen-------

  • outline focusing on Processes and Process States, Process Control Block (PCB), Context Switching, and Basic Shell Scripting:

    Topics:

    1. Processes and Process States:

       • Definition and Characteristics of a Process:

         • A process is an instance of a program that is being executed. It consists of program code, data, and resources (CPU time, memory, I/O devices).
         • Characteristics include process ID (PID), state, priority, CPU registers, and memory space.

       • States of a Process:

         • New: The process is being initialized.
         • Ready: The process is ready to execute and waiting for CPU time.
         • Running: The process is currently being executed.
         • Waiting: The process is waiting for some event (e.g., I/O completion).
         • Terminated: The process has finished execution.

       • Process Control Block (PCB):

         • PCB is a data structure maintained by the operating system for each process.
         • It includes process state, program counter (PC), CPU registers, CPU scheduling information, and memory management information.
         • PCB allows the OS to manage and track processes effectively.

    2. Context Switching:

       • Definition and Purpose of Context Switching:

         • Context switching is the process of saving the state of a process (PCB) so that it can be resumed later and loading the state of another process to run.
         • Purpose: Allows multitasking and efficient sharing of CPU resources among multiple processes.

       • Mechanisms Involved in Context Switching:

         • Involves saving the current state of the running process (registers, PC, etc.) into its PCB.
         • Loading the saved state of the next process from its PCB into the CPU registers.
         • Switching memory address spaces if processes belong to different address spaces (e.g., virtual memory).

       • Context Switch Overhead and Optimization:

         • Overhead: Context switching consumes CPU cycles and introduces latency due to saving and restoring process states.
         • Optimization strategies include using efficient scheduling algorithms (e.g., preemptive scheduling) to minimize context switches and optimizing the context switch routines.

    3. Basic Shell Scripting:

       • Introduction to Shell Scripting:

         • Shell scripting involves writing scripts (sequences of commands) in a shell (command-line interpreter) language.
         • Common shells include Bash (Bourne Again SHell) on Unix/Linux and Command Prompt on Windows.

       • Writing Simple Scripts:

         • Tasks include automating file operations (copying, moving, deleting), text processing (searching, parsing), and system administration tasks (monitoring system resources, setting up environments).

       • Use Cases and Advantages:

         • Automating repetitive tasks to save time and reduce errors.
         • Facilitating batch processing and system administration tasks.
         • Integrating with system utilities and commands to perform complex operations efficiently.

    Activities:

    • Lab: Writing Simple Shell Scripts

      • Task: Write shell scripts to automate common tasks such as file management, text processing, or system monitoring.
      • Objective: Gain hands-on experience with basic shell commands, scripting syntax, and understanding of process interaction in scripts.

    • Discussion Forum: Process States and Context Switching

      • Topic: Discuss the lifecycle of processes and the impact of context switching on system performance.
      • Points to Consider: How do different process states affect system resources? What are the challenges in managing context switches effectively?

    • Quiz: Understanding Processes and Shell Scripting

      • Format: Multiple-choice and short-answer questions.
      • Scope: Covers topics such as process states, PCB structure, context switching mechanisms, and basic shell scripting concepts.

    Recommended Resources:

    • Textbook: "Operating System Concepts" by Abraham Silberschatz, Peter B. Galvin, and Greg Gagne.
    • Additional Reading: "The Linux Command Line" by William Shotts, for practical guidance on shell scripting and command-line utilities.