Computer Architecture Questions
Cache coherence refers to the consistency of data stored in different caches that are part of a multiprocessor system. In a multiprocessor system, each processor has its own cache memory to store frequently accessed data. However, when multiple processors are accessing and modifying the same data, it can lead to inconsistencies and errors.
Cache coherence ensures that all processors in the system observe a consistent view of memory. It guarantees that any read operation on a memory location returns the most recent write operation on that location, regardless of which processor performed the write.
To maintain cache coherence, various protocols are used, such as the MESI (Modified, Exclusive, Shared, Invalid) protocol. These protocols allow processors to communicate and coordinate their cache operations, ensuring that all caches are updated with the latest data.
Cache coherence is crucial for maintaining data integrity and avoiding race conditions in multiprocessor systems. It allows for efficient sharing of data among processors while ensuring that all processors have a consistent view of memory.