Directory-based Cache Coherence

Directory-based cache coherence is a method used in computers to ensure all processors have a consistent view of shared data. A central directory keeps track of which caches hold copies of data items. When a processor updates data, it sends a message to the directory, which then coordinates to update or invalidate other caches' copies. This system prevents conflicts and ensures data accuracy across multiple processors, especially in complex, multi-core systems. It efficiently manages data sharing without needing direct communication between every cache, improving performance and maintaining consistency.