Multiprocessors and Thread-Level Parallelism 1. Explain Symmetric Shared-Memory Architecture and How to reduce Cache coherence problem in Symmetric Shared Memory architectures: Symmetric Shared Memory Architectures: The Symmetric Shared Memory Architecture consists of several processors with a single physical memory shared by all processors through a shared bus which is shown below.
Small-scale shared-memory machines usually support the caching of both shared
and private data. Private data is used by a single processor, while shared data is used by multiple processors, essentially providing communication among the processors through reads and writes of the shared data. When a private item is cached, its location is migrated to the cache, reducing the average access time as well as the memory bandwidth required. Since no other processor uses the data, the program behavior is identical to that in a uniprocessor.
Cache Coherence in Multiprocessors: Introduction of caches caused a c..