Patent ID: 6513093
Filing Date: 2003-01-28
Classification: G06F

Abstract:
A general purpose computer including at least one memory and at least one computer usable medium having computer usable code means for storing data on at least one data storage device having at least one old data set stored thereon, the computer usable code means including:computer readable code means for receiving an update of at least a portion of the old data set; computer readable code means for modifying, in memory, the old data set using the update, to render a modification; computer readable code means for writing at least a record of the modification to a log; and computer readable code means for writing at least a portion of the modification to the data storage device, wherein the portion of the old data is at least plural old strips of a stride, the update is at least plural new strips, the computer readable code means for writing the modification to the data storage device writes the modification to a new physical location on the data storage device that is different from the physical location of the old data set, and the computer usable code means includes: computer readable code means for generating at least one new parity strip using at least the new strips, wherein the means for writing the record to the log also writes at least an address of the new physical location and an address of the physical location of the old data set to the log, without writing the modification and the new parity strip to the log.