Concurrency and Synchronization Questions

Covers the principles and practical techniques for safely coordinating concurrent execution and access to shared resources. Topics include models of concurrency such as threads, processes, interrupt handlers, and tasks in a real time operating system; differences between preemptive and cooperative scheduling; shared data hazards including race conditions and read modify write hazards; critical sections and approaches to protect them including disabling interrupts in embedded contexts and scoped locks. Synchronization primitives and patterns are included: mutexes, binary semaphores, counting semaphores, condition variables, message queues, atomic operations and lock free primitives such as compare and swap. Memory ordering concerns and memory barrier usage on multi core systems are covered, along with priority inversion and priority inheritance. Also addressed are deadlock, livelock, and starvation concepts and avoidance strategies, granularity and performance trade offs of locking, and practical synchronization patterns. Preparation should include identifying and fixing races in code, designing correct concurrent interfaces, and debugging and testing techniques such as stress testing, instrumentation, deterministic replay, race detectors, static analysis, and code review strategies.