🌐 Introduction to Process Management
Process Management is a fundamental function of an operating system (OS) that handles the creation, scheduling, execution, and termination of processes. It ensures that multiple programs can run efficiently and concurrently on a computer system.
In simple terms:
Process management = controlling and coordinating program execution
A process is a program in execution, including its code, data, and state.
🧠 Importance of Process Management
- Enables multitasking
- Optimizes CPU utilization
- Ensures fair resource allocation
- Maintains system stability
- Improves performance
🧩 Basic Concepts
📄 Program vs Process
| Feature | Program | Process |
|---|---|---|
| Definition | Static code | Executing program |
| State | Passive | Active |
| Example | .exe file | Running application |
🔁 Process States
A process moves through different states:
- New – Being created
- Ready – Waiting for CPU
- Running – Executing
- Waiting (Blocked) – Waiting for I/O
- Terminated – Finished execution
🧠 Process Control Block (PCB)
PCB stores process information:
- Process ID (PID)
- Process state
- CPU registers
- Memory allocation
- Scheduling information
⚙️ Process Scheduling
🧠 What is Scheduling?
Scheduling determines which process gets CPU time.
🔁 Types of Schedulers
- Long-term scheduler – selects processes
- Short-term scheduler – allocates CPU
- Medium-term scheduler – swaps processes
⚡ Scheduling Algorithms
🔹 1. First Come First Serve (FCFS)
- Processes executed in arrival order
🔹 2. Shortest Job First (SJF)
- Shortest execution time first
🔹 3. Round Robin (RR)
- Time-sharing system
- Each process gets fixed time slice
🔹 4. Priority Scheduling
- Processes executed based on priority
⚖️ Scheduling Criteria
- CPU utilization
- Throughput
- Turnaround time
- Waiting time
- Response time
🔄 Process Synchronization
🧠 Concept
Ensures safe access to shared resources.
⚠️ Critical Section Problem
- Section where shared data is accessed
🔒 Solutions:
- Mutex locks
- Semaphores
- Monitors
⚠️ Deadlocks
🧠 Definition
Deadlock occurs when processes wait indefinitely.
🔑 Conditions:
- Mutual exclusion
- Hold and wait
- No preemption
- Circular wait
🔄 Handling Deadlocks:
- Prevention
- Avoidance
- Detection and recovery
🔁 Inter-Process Communication (IPC)
📡 Methods
- Shared memory
- Message passing
- Pipes
- Sockets
🧠 Threads and Multithreading
🔹 Threads
- Lightweight processes
- Share memory
⚡ Benefits:
- Faster execution
- Better resource utilization
🔄 Context Switching
🧠 Concept
- CPU switches between processes
- Saves and loads state
🧩 Process vs Thread
| Feature | Process | Thread |
|---|---|---|
| Memory | Separate | Shared |
| Overhead | High | Low |
| Speed | Slower | Faster |
⚙️ Multiprocessing
🧠 Concept
- Multiple CPUs/cores
- Parallel execution
🧠 Real-Time Process Management
⚡ Types:
- Hard real-time
- Soft real-time
Used in:
- Robotics
- Embedded systems
🔐 Process Security
🛡️ Features:
- Access control
- Isolation
- Sandboxing
⚡ Performance Optimization
- Efficient scheduling
- Load balancing
- Minimizing context switches
⚠️ Challenges
- Deadlocks
- Starvation
- Race conditions
🚀 Modern Trends
- Containerization
- Virtualization
- Cloud computing
- Microservices
🧾 Conclusion
Process management is a core function of operating systems that ensures efficient execution of programs. It enables:
- Multitasking
- Resource sharing
- System stability
Understanding process management is essential for:
- OS design
- Software development
- Performance optimization