CACHE APPARATUS AND CONTROL METHOD ALLOWING SPECULATIVE PROCESSING DATA

The invention relates to cache apparatuses and a control method for managing cache memories in a multiprocessor system. A cache controller holds data which has to be invalidated for a cache coherence as data in a status where the validity is unknown, causes a cache hit in response to a reading request from a processor, provides the data as speculation data, and allows the processor to speculatively process the data. Therefore, since the data which has to be obtained from another cache or a main storage due to the invalidation is held in an Unknown status, a cache hit occurs. Thus, a data waiting time of the processor can be shortened.