| 摘要 |
<P>PROBLEM TO BE SOLVED: To propose a storage device and a data hierarchy management method for promoting the valid use of a storage device while suppressing costs and labors necessary for maintenance. <P>SOLUTION: A storage device for dynamically assigning a storage area in response to a write request from a host device to a virtual volume is provided with a control part for monitoring the access frequency of every unit area of the virtual volume, and for executing the shift of data in order to assign the storage area which is higher in responsiveness to the unit area whose access frequency is high. When shifting the data from a first storage area provided by a first storage device whose rewritable frequency is limited to a second storage area provided by the other second storage device, the control part does not delete the data from the first storage area, but overwrites only an update section updated after the data are shifted to the second storage area on the corresponding data remaining in the first storage area in case of returning the data from the second storage area to the first storage area. <P>COPYRIGHT: (C)2012,JPO&INPIT |
