sentence: Cache coherence is there to manage such conflicts and maintain consistency between cache and memory.
sentences_before: There may be problems if there are many caches of a common memory resource, as data in the cache may no longer make sense, or one cache may no longer have the same data as the others. A common case where the problem occurs is the cache of CPUs in a multiprocessing system. As can be seen in the figure,  if the top client has a copy of a memory block from a previous read and the bottom client changes that memory block, the top client could be left with an invalid cache of memory,without knowing.
concept_name: cache coherence
headings: Cache coherence
categories: Computer science