Lecture Notes: Process and Thread Management in Operating Systems

Introduction

• Previous lectures focused on:
  • Introduction to Operating System
  • Operating System Structures
• Current topic: Process Management

Key Concepts

Programs and Execution

• Program Development:
  • Written in high-level languages (e.g., C, C++, Java).
  • Must be converted to machine code (binary) for execution.
  • Compiler used to compile programs into machine code.
• Execution Requirements:
  • The binary executable must be loaded into memory.
  • The Operating System (OS) allocates necessary resources for execution.

Processes

• Definition:
  • A process is a program in execution.
  • Before execution, a program is a passive entity.
• Historical Context:
  • Early computers supported only one process at a time.
  • Modern computers support multiple processes simultaneously.
• Characteristics:
  • A single program can have multiple associated processes.

Threads

• Definition:
  • A thread is the basic unit of execution within a process.
  • A process can have one or multiple threads.
• Historical Context:
  • Earlier systems typically had one thread per process.
  • Modern systems allow multiple threads within a single process.

Visualization of Processes and Threads

• Diagram Explanation:
  • Entirely, a process consists of one or more threads of execution.
  • Each unit of execution is a thread.

Practical Example: Monitoring Processes and Threads

Task Manager (Windows)

• To view running processes:
  • Open Task Manager.
  • Check the Applications and Processes tabs for active programs and processes.
• Example:
  • Chromium browser running several processes (e.g., chrome.exe).

Process Explorer

• Additional tool for detailed analysis:
  • Displays processes and their associated threads.
  • To find threads:
    • Right-click on a process (e.g., chrome.exe) and check properties.
    • View the Threads tab for detailed thread information.

Conclusion

• Recap of processes and threads:
  • Important to differentiate between the two.
  • Process management is a crucial aspect of operating systems.
• Upcoming lectures will delve deeper into processes and related topics.