Patent ID: 8145605

Claim:
A storage system comprising: one or more file systems configured to store data; and a processor configured to: produce snapshots for the file systems based on a pre-scheduled snapshot acquisition time, execute remote copy of difference data for the snapshots based on pre-scheduled remote copy start times, if the processor estimates that an Nth remote copy of the difference data of snapshots will not be completed by an (N+1)th remote copy start time, re-schedule a time of one or more of an Nth snapshot acquisition time, an Nth remote copy start time, and an (N+1)th remote copy start time, and if re-schedule of the time is still insufficient to permit completion of the Nth remote copy before the Nth remote copy is executed, thin out an amount of the difference data for the snapshot, wherein the processor is configured to estimate the amount of difference data for a snapshot of the file system acquired the Nth remote copy based on an amount of difference data for a snapshot of the file system acquired an (N−1)th remote copy, and to execute the re-scheduling based on the estimated amount of difference data.