Multithreading Programming in C++ Training Course

Challenges and problems of concurrency

• Hardware limitations of platforms - hardware threads, pipelines, cache coherence
• Fundamental concepts related to multithreaded programming (correctness of multithreaded programs, liveness, starvation, deadlock, race conditions, atomicity, memory models, Flynn's taxonomy)
• Available C++ mechanisms for implementing multithreading and multiprocessing
• Standard library implementation - elements from C++14 to the present day (C++2a)
• Implementation available in Boost - differences compared to the standard library

Processes and threads

• Multiprocess vs multithreaded applications
• Operating system and threads (short overview of available implementations)
• Mechanisms for process and thread synchronization
• Structural implementation of synchronization
• Specifics of multithreading implementation in an object-oriented approach (role of the RAII pattern)

Memory model in C++

• Objects and memory locations
• Operation scheduling and enforcement
• Relations: synchronization, before, ordering of operations for atomic actions, release sequences
• Memory barriers
• Atomic operations

Thread management in C++14 and newer standards

• std::thread class and thread execution
• Thread identification
• Attaching and detaching threads
• Threads and standard containers
• Exception handling in C++14 threads

Mutual exclusion and critical sections

• Basic rules of mutual exclusion
• Concepts (types) of available locking objects
• Quick introduction to time handling in C++14 (chrono library)
• std::mutex, std::timed_mutex, std::shared_mutex classes and derived classes
• RAII pattern in lock handling (std::lock_guard, std::unique_lock)
• Dependent and deferred locks (std::lock)
• Ownership and co-ownership of locks and threads
• Readers-writers problem
• One-time initialization
• Thread-local (private) memory (std::thread_local)

Locks and thread synchronization

• Semaphore operations
• Recursive locks
• Locks with defined locking level
• Decision variables and cooperation with locks
• Implementation of active and passive barriers (Idle Waits, Busy Waits)
• Thread resumption
• Communication between threads (Actor and CSP models)

Asynchronous tasks

• Asynchronous events and their handling
• Futures
• Promises
• Packaged tasks

Atomic types

• Standard atomic types
• Universal atomic flag (std::atomic_flag)
• Template class 'std::atomic<T>' and its specializations
• Utility functions (free) of std::atomic types

Specifics of designing multithreaded APIs

• Designing structures using locks - coarse and fine-grained locks
• Efficiency of concurrent code - estimation and measurement techniques
• Data partitioning
• Scalability of solutions
• Error and exceptional situation handling in application architecture

Testing and debugging multithreaded applications

• Code reviews for multithreaded operations
• Specifics of testing multithreaded applications
• Unit tests
• Increasing the probability of failure scenarios for testing
• Formal methods for testing multithreaded applications
• Multithreaded application architecture patterns and testing and debugging (overview)

Advanced thread management

• Dependent threads (Saga pattern)
• Avoiding data access competition
• Controlled thread stop and interruption
• Interrupting blocking calls
• Handling interruption
• Task stealing
• Interrupting tasks during application shutdown

Multithreading design patterns

• Types and purpose of multithreading patterns
• Scope of pattern application
• Thread Pool
• Active Object pattern
• Thread Safe Queue
• Producer-Consumer pattern
• Monitor pattern
• Multithreading safety of GoF patterns