Cache Coherence: Basics and Protocols

This lecture covers the fundamentals of cache coherence, focusing on the challenges of maintaining data consistency across multiple processors. It explains the concepts of hardware cache coherence, memory hierarchy, and the principles of locality. The instructor discusses the incoherence problem that arises when multiple cores access and update shared data concurrently. Various cache coherence protocols, such as MSI and MESI, are explored, along with their mechanisms and state diagrams. The lecture also delves into the implementation of directory-based coherence protocols to reduce bus contention and improve scalability in multi-core systems.