Storage system and data relocation method

A system according to 5, wherein said logical disk relocation control means obtains an I/O request arrival rate and a busy rate from statistical information measured every second time interval shorter than a first time interval during which periodicity is observed in a data access pattern.

A system according to 11, wherein said logical disk relocation control means obtains an I/O request arrival rate and a busy rate from statistical information measured every second time interval shorter than a first time interval during which periodicity is observed in a data access pattern.

A data relocation method in a storage system which relocates a plurality of logical disks constituted by combining a plurality of physical disks, comprising the steps of:

• obtaining a ratio of input/output (I/O) request arrival rates of the physical disks;
• and
• relocating the logical disks so as to set the obtained ratio of the I/O request arrival rates to an Nth (N is a real number of not smaller than 1 and not larger than 2) power ratio of I/O processing performance values of the physical disks.

A data relocation method in a storage system which relocates a plurality of logical disks constituted by combining a plurality of physical disks, comprising the steps of:

• calculating an average of processing standby times serving as a value obtained by averaging standby times of the physical disks until start of processing corresponding to I/O requests by using either one of a first group including I/O processing performance values, I/O request arrival rates, and busy rates of the physical disks, and a second group including the I/O processing performance values and the I/O request arrival rates of the physical disks;
• and
• relocating the logical disks so as to minimize the calculated average of the processing standby times.

A method according to 17, wherein the relocating step comprises the step of obtaining an I/O request arrival rate and a busy rate from statistical information measured every second time interval shorter than a first time interval during which periodicity is observed in a data access pattern.

A data relocation method in a storage system which relocates a plurality of logical disks constituted by combining a plurality of physical disks, comprising the steps of:

• calculating an average of response times serving as a value obtained by averaging time intervals of the physical disks between arrival of I/O request processing at the physical disks and end of the I/O request processing by using either one of a first group including I/O processing performance values, I/O request arrival rates, and busy rates of the physical disks, and a second group including the I/O processing performance values and the I/O request arrival rates of the physical disks;
• and
• relocating the logical disks so as to minimize the calculated average of the response times.

A method according to 23, wherein the relocating step comprises the step of obtaining an I/O request arrival rate and a busy rate from statistical information measured every second time interval shorter than a first time interval during which periodicity is observed in a data access pattern.

A computer-readable recording medium which records a data relocation program in a storage system which relocates a plurality of logical disks constituted by combining a plurality of physical disks, wherein the data relocation program comprises programs which execute procedures of:

• obtaining a ratio of input/output (I/O) request arrival rates of the physical disks;
• and
• relocating the logical disks so as to set the obtained ratio of the I/O request arrival rates to an Nth (N is a real number of not smaller than 1 and not larger than 2) power ratio of I/O processing performance values of the physical disks.

A computer-readable recording medium which records a data relocation program in a storage system which relocates a plurality of logical disks constituted by combining a plurality of physical disks, wherein the data relocation program comprises programs which execute procedures of:

• calculating an average of processing standby times serving as a value obtained by averaging standby times of the physical disks until start of processing corresponding to I/O requests by using either one of a first group including I/O processing performance values, I/O request arrival rates, and busy rates of the physical disks, and a second group including the I/O processing performance values and the I/O request arrival rates of the physical disks;
• and
• relocating the logical disks so as to minimize the calculated average of the processing standby times.

A computer-readable recording medium which records a data relocation program in a storage system which relocates a plurality of logical disks constituted by combining a plurality of physical disks, wherein the data relocation program comprises programs which execute procedures of:

• calculating an average of response times serving as a value obtained by averaging time intervals of the physical disks between arrival of I/O request processing at the physical disks and end of the I/O request processing by using either one of a first group including I/O processing performance values, I/O request arrival rates, and busy rates of the physical disks, and a second group including the I/O processing performance values and the I/O request arrival rates of the physical disks;
• and
• relocating the logical disks so as to minimize the calculated average of the response times.