Patent ID: 6128699
Filing Date: 2000-10-03
Classification: G06F

Abstract:
A storage system for storing data records, said storage system comprising a system controller and a plurality of storage devices, each of said storage devices comprising:a storage medium for storing data records, said data records being indexed by addresses which specify the location of said data records in said storage medium;a disk controller for receiving write messages from processors coupled to said controller, each write message including a data segment to be written to said storage medium at a specified address, and a linkage record specifying a timestamp, the addresses of other data records on other storage devices that were written in the same write operation, and the original source of said data segment; anda log for storing said linkage records and associating each of said linkage records with said data segment that was received with said linkage record,wherein said system controller is responsive to a copy-write message specifying a source region on one of said storage devices, the ""source"", that is to be copied to a target region on one of said storage devices, the ""target"", said copy-write message specifying said source region, said target region, and said target,said copy-write message causing said system controller to read said source region and said linkage records associated therewith, modify said associated linkage records to indicate that said source region on said target is the original source of said source region if said source region was not created by a previously executed copy-write message, and to write said source region and said associated linkage records, including any modifications thereto, to said target via one of said write messages.