Concurrency & Parallelism

Fundamentals

Core concepts that form the foundation of concurrent systems.

1. Basic Concepts

• Sequential execution
• Concurrent execution
• Parallel execution
• Asynchronous execution
• Synchronous vs Asynchronous
• Blocking vs Non-blocking
• CPU-bound vs I/O-bound tasks

2. Motivation

• Performance improvement
• Responsiveness
• Resource utilization
• Scalability

Process & Thread Basics

Understanding execution units and their models.

3. Processes

• Process creation
• Process states
• Process switching
• Inter-process isolation

4. Threads

• Threads vs Processes
• User threads vs Kernel threads
• Multithreading models
• Thread lifecycle

Concurrency Models

Different approaches to managing concurrent execution.

5. Concurrency Models

• Shared memory model
• Message passing model
• Actor model
• Event-driven model
• Reactive model

6. Event Loop Model

• Single-threaded concurrency
• Task queue
• Microtask queue
• Callback queue

Synchronization

Managing shared resources and coordinating execution.

7. Critical Section Problem

• Race conditions
• Data inconsistency

8. Synchronization Mechanisms

• Mutex
• Semaphore
• Read-write locks
• Spinlocks
• Monitors
• Condition variables

9. Atomic Operations

• Compare-and-swap (CAS)
• Lock-free programming basics

Common Concurrency Problems

Classic challenges in concurrent programming.

10. Classic Problems

• Producer–Consumer
• Dining Philosophers
• Readers–Writers

11. Deadlocks

• Necessary conditions
• Prevention
• Avoidance
• Detection
• Recovery

12. Livelock & Starvation

• Livelock definition
• Starvation causes

Parallelism Fundamentals

Leveraging multiple processors and cores.

13. Parallel Computing Basics

• Data parallelism
• Task parallelism
• Pipeline parallelism

14. Hardware Parallelism

• Multi-core CPUs
• SIMD
• GPU parallelism basics

Language & Runtime Level

Concurrency abstractions provided by programming environments.

15. Runtime Concurrency

• Thread pools
• Worker pools
• Futures & promises
• Async/Await patterns

16. Memory Models

• Memory visibility
• Happens-before relationship
• Memory barriers

System-Level Concurrency

OS-level concurrency management.

17. OS Scheduling

• Context switching
• Time slicing
• Preemptive scheduling

18. I/O Concurrency

• Non-blocking I/O
• Event-driven servers
• Polling vs Interrupt-driven

Distributed Concurrency

Concurrency across multiple systems.

19. Distributed Systems Basics

• Distributed locks
• Consensus basics
• Leader election
• Eventual consistency

20. Message Systems

• Message queues
• Pub/Sub model
• Stream processing

Production & Architecture Level

Real-world concurrency concerns and patterns.

21. Concurrency in Web Systems

• Concurrent API handling
• Rate limiting
• Backpressure

22. Parallel Processing Systems

• MapReduce basics
• Batch vs Stream processing

23. Observability

• Race condition debugging
• Thread profiling
• Performance monitoring