Multithreading Programming in C++ Training Course

Concurrency Challenges and Problems

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

Processes and Threads

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

Memory Model in C++

• Objects and memory locations
• Sequencing operations and enforcing order
• Relations: synchronization, happens-before, ordering operations for atomic actions, release sequences
• Memory barriers
• Atomic operations

Thread Management in C++14 and Later Standards

• The std::thread class and thread launching
• Thread identification
• Thread joining and detaching
• Threads and standard containers
• Exception handling in C++14 threads

Mutual Exclusion and Critical Sections

• Basic principles of mutual exclusion
• Concepts (types) of available locking objects
• A quick introduction to time handling in C++14 (chrono library)
• std::mutex, std::timed_mutex, std::shared_mutex classes and derivatives
• The RAII pattern for lock handling (std::lock_guard, std::unique_lock)
• Dependent and deferred locks (std::lock)
• Ownership and shared ownership of locks and threads
• The readers-writers problem
• Once-only initialization
• Thread-local (private) memory (std::thread_local)

Locks and Thread Synchronization

• Semaphore operations
• Recursive locks
• Locks with defined lock levels
• Condition variables and cooperation with locks
• Implementation of active and passive barriers (Idle Waits, Busy Waits)
• Resuming thread execution
• Inter-thread communication (Actor model and CSP)

Asynchronous Tasks

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

Atomic Types

• Standard atomic types
• Universal atomic flag (std::atomic_flag)
• The "std::atomic<T>" class template and its specializations
• Utility (free) functions for std::atomic types

Specifics of Multithreaded API Design

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

Testing and Debugging Multithreaded Applications

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

Advanced Thread Management

• Dependent threads (Sagi pattern)
• Avoiding data access contention
• Controlled thread suspension and interruption
• Interrupting blocking calls
• Handling interruptions
• Task stealing
• Interrupting tasks during application shutdown

Multithreading Design Patterns

• Types and purposes of multithreaded patterns
• Scope of pattern application
• Thread Pool
• Active Object pattern
• Thread Safe Queue
• Producer-Consumer pattern
• Monitor pattern
• Multithread safety of GoF patterns