The present invention is a system for optimizing the reconstruction and copyback of data contained on a failed disk in a multi-disk mass storage system.A system in accordance with the present invention may comprise the following: a processing unit requiring mass-storage; one or more disks configured as a RAID system; an associated global hot spare disk; and interconnections linking the processing unit, the RAID and the global hot spare disk.In a further aspect of the present invention, a method for the reconstruction and copyback of a disconnected RAID disk utilizing a global hot spare disk is disclosed. The method includes: disconnecting a RAID component disk; reconstructing data from the disconnected RAID disk onto a global hot spare disk; reconnecting the disconnected RAID component disk; and copying the reconstructed data from the global hot spare disk back to the reconnected RAID component disk.