Large capacity storage apparatus having storage cells, an accessor, a cache memory and a disc update section to set a number of frequently accessed storage media

摘要

Data is stored in a cache memory, a cache HDD, high frequently accessed optical discs, or low frequently accessed optical discs, and the data is transferred between the cache memory and the cache HDD under the control of a control device which predicts the access frequency of data on the basis of the access history, transfers modified data items and only data items frequently accessed and not allocated to a high frequently accessed optical disc from the cache memory to the cache HDD, and deletes the remaining, thereby improving the use efficiency of the cache HDD.