Patent ID: 7133987
Filing Date: 2006-11-07
Classification: G06F,Y10S

Abstract:
1. A storage system having a first volume and a second volume, the storage system comprising, for when it has received a snapshot acquisition request from a computer requesting the taking of a snapshot of the first volume pertaining to a designated time: first synchronous copying means for, after the designated time, receiving a data access request from the computer with a storage region in the first volume as a target, and, if data recorded in the target storage region in the first volume has not been copied to the second volume since the designated time, copying data recorded in the target storage region to the second volume; and first advance copying means for, after the designated time, predicting a storage region in the first volume to be the target of a data access request from the computer in the future, and, if data recorded in the predicted storage region has not been copied to the second volume since the designated time, copying data recorded in the predicted storage region to the second volume in response to said first synchronous copying means receiving said data access request from the computer.