| 摘要 |
PROBLEM TO BE SOLVED: To provide a RAID system that enables a drop in performance of a hard disk drive (HDD) to be easily detected .SOLUTION: In a RAID system including one hard disk drive of a disk 1, a disk 2, ..., and a disk n or a plurality of hard disk drives (HDD) thereof, when receiving an IO request from a host device in a normal operation time, the RAID system is configured to: measure an elapsed time until an IO response from the hard disk drive is returned since an IO command is issued to a hard disk drive (HDD) of the IO command issue object; store the measured elapsed time in a timer recording area 22; and, when the elapsed time stored in the timer recording area 22 reaches a predetermined time threshold value or more, register and store performance drop information indicative of occurrence of a drop in performance of the hard disk drive as log data in a performance drop information registration table 23. |
