Patent ID: 7506101
Filing Date: 2009-03-17
Classification: G06F

Abstract:
1. A data migration method for migrating data from a source logical volume to a target logical volume in one or more storage systems including a plurality of parity groups, each of said parity groups including logical volumes configured by physical storage devices, the method comprising: obtaining an access source performance, which is a performance of an access source of a logical volume, for each of a plurality of access sources; obtaining a volume performance, which is a performance of a logical volume, for each logical volume; selecting a source volume sub-candidate from said plurality of logical volumes on the basis of said obtained access source performance of each access source and said obtained volume performance of each logical volume; identifying a parity group to which said selected source volume sub-candidate belongs from said plurality of parity groups; identifying access sources of the identified parity group from said plurality of access sources; calculating a degree of performance degradation for each of a plurality of access pairs, which are pairs constituted by each access source and the logical volume serving as the access destination thereof, on the basis of (1) a total access source performance which is a sum total of access source performances corresponding respectively to said identified access sources, and (2) a parity performance which is a sum total of volume performances corresponding respectively to the logical volumes belonging to said certain parity group; setting a logical volume of an access pair, whose calculated degree of performance degradation exceeds a predetermined value, as said source volume sub-candidate; selecting one of source volume sub-candidates belonging to said identified parity group, and selecting a target volume from said plurality of logical volumes which has a volume performance greater than a volume performance of said one source volume sub-candidate; and migrating data from said one source volume sub-candidate to said selected target volume, wherein said degree of performance degradation for a single access pair=the volume performance of the logical volume constituting said access pair×an efficacy ratio—the access source performance of the access source constituting said access pair, and said efficacy ratio=said parity performance/said total access source performance.