Analyze the following hypothetical legacy code scenario involving a shared global counter accessed by multiple threads without synchronization: [Snippet: global count = 0; function increment() { count = count + 1; }]. Identify specific race conditions and potential deadlocks that could arise in a high-load environment. Propose a refactored solution using modern concurrency patterns (e.g., mutexes, atomic operations, or actor models) that ensures thread safety without introducing significant performance bottlenecks. Explain the trade-offs of your chosen approach.