Thread Definition
- Lightweight execution unit within a process
- Enables concurrent operations within a single program
- Shares process resources while executing independently
Key Characteristics
- Lightweight compared to full processes
- Share memory and resources with parent process
- Enable parallel/concurrent execution
- Independent yet process-dependent execution
Thread vs Process
| Aspect | Thread | Process |
|---------------|---------------------|---------------------|
| Memory | Shared | Private |
| Creation Cost | Low | High |
| Communication | Direct | Requires IPC |
| Failure Impact| Affects whole process| Isolated |
Thread Lifecycle
- New → 2. Runnable → 3. Running → 4. Blocked → 5. Terminated
Applications
- Performance enhancement
- Parallel programming
- Responsive GUIs
- Web servers
- Data processing
Advantages
✔ Increased speed
✔ Efficient resource usage
✔ Better responsiveness
✔ Lower system overhead
✔ Simplified inter-thread communication
Challenges
Complex programming- Synchronization issues (deadlocks, race conditions)- Resource consumption- Difficult debugging- Architecture dependence
Thread Implementation
- Java : Thread class, Executor
- Python : threading module
- C/C++ : pthread library
- C# : System.Threading namespace
Special Types
- Green Threads : VM-managed rather than OS-managed
Multithreading Benefits
- Improved multi-core utilization
- Maintained UI responsiveness during heavy processing
- Logical task division
Thread Components
- Thread ID
- Program Counter
- Thread Stack
- Shared Memory
- Registers
- State
- Thread Control Block (TCB)
Threads are powerful for concurrent execution but require careful management. With multi-core processors becoming standard, proper thread synchronization and resource management are essential for developing efficient applications.