HIERARCHICAL STORAGE SYSTEM PROVIDED WITH TRIAL AREA, STORAGE CONTROLLER, AND PROGRAM

摘要

A hierarchical storage system according to an embodiment of the present invention is provided with: a first storage device; a second storage device that has a lower access speed and a larger storage capacity than the first storage device; and a storage controller. The storage controller is provided with a first rearrangement unit and a second rearrangement unit. The first rearrangement unit switches the arrangement destination of the data of a first logical chunk to which a third storage area of the second storage device is allocated with the arrangement destination of the data of a second logical chunk that has a smaller access frequency statistic value than the first logical chunk and to which a first storage area of the first storage device is allocated. The second rearrangement unit reallocates a second storage area of the first storage device to a logical chunk set to which the third storage area is allocated.