Management system and methods of storage system comprising pool configured of actual area groups of different performances

A management system of a storage system, which receives an access command from an access source,

• wherein the storage system comprises multiple virtual volumes, multiple pools, and a controller,
• wherein each virtual volume is a virtual logical volume configured of multiple virtual areas,
• wherein each pool is a storage area configured of multiple actual area groups of different performances,
• wherein the controller,
• (a) receives the access command,
• (b) accesses an actual area in a case where this actual area has not been assigned to a virtual area identified from the access command, and
• (c) in a case where an actual area is not assigned to the identified virtual area, assigns an actual area from a pool, from among the multiple pools, which has been made to correspond to a virtual volume having the identified virtual area, and accesses the assigned actual area, and
• wherein the controller manages pool condition information, which is information showing which actual area is assigned to which virtual area and showing an access load related to a virtual area,
• wherein the management system comprises:
• a storage resource;
• and
• a processor coupled to this storage resource,
• wherein the storage resource stores, with respect to each virtual volume, management information showing a performance requirement related to an access from the access source to the virtual volume and a performance related to an access from the access source to the virtual volume,
• wherein performance of the virtual volume is performance identified based on the pool condition information, and
• wherein the processor,
• (A) identifies, based on this management information, a virtual volume whose condition is inappropriate from among the multiple virtual volumes, and
• (B) performs a migration procedure related to the pool that has been made to correspond to the identified virtual volume to change the condition of the identified virtual volume from the inappropriate condition to an appropriate condition;
• and:
• wherein the migration process performed in the (B) is for adding a first storage capacity from another pool to the pool that has been made to correspond to the virtual volume identified in the (A),
• wherein the first storage capacity is a storage capacity in excess of the performance of the virtual volume that has been made to correspond to an other pool, and, in addition, is a storage capacity that is equal to or greater than a second storage capacity, and
• wherein the second storage capacity is a storage capacity added to the pool that has been made to correspond to the virtual volume identified in the (A) so that the performance of the virtual volume identified in the (A) satisfies the performance requirement of this virtual volume.