Disk array optimizing the drive operation time

In a method used in a computer system which comprises:

• a storage system including a first disk device configuring a first logical unit, a second disk device configuring a second logical unit, and a controller for accessing to the first logical unit and the second logical unit;
• and
• a disk controller requesting an access to the first logical unit and the second logical unit and a disk power supply control circuit instructing the controller to turn on or off the first disk device configuring the first logical unit and the second disk device configuring the second logical unit,
• the method comprising steps of:
• issuing an instruction to turn off the first disk device configuring the first logical unit to the controller by the disk power supply control circuit, after the disk power supply control circuit determines that the disk controller terminates requesting the access to the first logical unit;
• and
• turning off the first disk device configuring the first logical unit independently of the second disk device configuring the second logical unit based on the instruction by the controller;
• wherein the disk controller is configured to request an access to the second logical unit after a completion of accessing to the first logical unit, and
• the method further comprising steps of:
• determining by the disk power supply control circuit whether or not the remaining time until a scheduled time of terminating the access to the first logical unit is shorter than a predetermined time;
• and
• instructing the controller to turn on the second disk device configuring the second logical unit, when the remaining time becomes shorter than a predetermined time.

A computer program product used in a computer system, wherein the computer system includes:

• a storage system including a first disk device configuring a first logical unit, a second disk device configuring a second logical unit, and a controller for accessing to the first logical unit and the second logical unit;
• and
• a disk controller accessing to the first logical unit and second logical unit, the computer program product comprising:
• a recording medium;
• a disk controller means, recorded on the recording medium, for requesting an access to the first logical unit and the second logical unit;
• and
• a disk power supply control means, recorded on the recording medium, for instructing the controller to turn on or off the first disk device configuring the first logical unit and the second disk device configuring the second logical unit,
• wherein after the disk power supply control means determines that the disk controller means terminates requesting the access to the fist logical unit, the disk power supply control means issues an instruction to turn off the first disk device configuring the first logical unit to the controller,
• wherein, based on the instruction, the controller turns off the first disk device configuring the first logical unit independently of the second disk device configuring the second logical unit,
• wherein the disk controller means is configured to request an access to the second logical unit after a completion of accessing to the first logical unit,
• wherein the disk supply instruction means determines whether or not remaining time until a scheduled time of terminating the access to the first logical unit is shorter than a predetermined time, and
• wherein when the remaining time becomes shorter than a predetermined time, the disk power supply control means instructs the controller to turn on the second disk device configuring the second logical unit.