Patent ID: 7577805

Claim:
In a storage system having a primary storage system and a secondary storage system, a method of providing a copy comprising: recording data in the primary storage system; at the primary storage system, storing a record of changes made during the step of recording data in the primary storage system; at the secondary storage system, issuing a request for reading the record of changes made during the step of recording data in the primary storage system; sending the record of changes made during the step of recording data in the primary storage system, to the secondary storage system; recording the record of changes made during the step of recording data in the primary storage system, at the secondary storage system; and using the record of changes made during the step of recording data in the primary storage system to thereby make a copy at the secondary storage system, wherein prior to the step of recording data in the primary storage system steps are performed comprising: forming a plurality of journal groups, each journal group including at least one pair of a primary volume from the primary storage system and a secondary volume from the secondary storage system, each journal group further including a primary journal volume for storage of journal data representing record of changes of the at least one primary volume in the journal group and a secondary journal volume for storage of copies of the journal data stored in the primary journal volume, each journal group configured to maintain consistency of data between each pair of the at least one pair of primary volume and secondary volume; for each of the plurality of journal groups, determining a capacity and a bandwidth for the primary and secondary journal volumes in said each journal group based on a designated quality of service parameter at a level designated for said each journal group; and for each of the plurality of journal groups, determining a maximum capacity rate for the primary and secondary journal volumes in said each journal group based on the bandwidth and the designated quality of service parameter for said each journal group.