To predict materials to request access later on material access conditions and to enable these materials to continuously exist in a buffer by dividing the cache buffer into least recently used(LRU) and least frequently used(LFU) areas and classifying a requested object to a hot set and a cold set.
The cache buffer in fixed size is divided into an LFU area 42 and an LRU area 43 and the sizes of these areas 42 and 43 are dynamically operated. Namely, when there are a lot of objects belonging to the hot set, the LFU area 42 is made relatively larger than the LRU area 43 and when an opposite phenomenon occurs with the passage of time, the LRU area 43 is enlarged in comparison with the LFU area 42. Further, the objects classified into the hot set and the objects classified into the cold set are linked by groups. Thus, the materials to request access later can be predicted on the material access conditions and can be let exist in the cache buffer.
BOKU YUKEI
KYO DAIEI
