Patent ID: 7219259

Claim:
A method to protect data integrity during loss of power to an information storage and retrieval system, comprising the steps of: providing an information storage and retrieval system comprising information comprising (N) first sectors written in a first sector format, a device controller, a data storage device, wherein said data storage device comprises an information storage medium comprising (M) second sectors each comprising a second sector format, a sector format conversion device, a communication link interconnecting said sector format conversion device and said device controller, wherein said sector format conversion devices is interconnected with said data storage device; sending the (i)th first sector to said sector format conversion device, wherein (i) is initially set to 1, and wherein (i) is greater than or equal to 1 and less than or equal to (N); overlaying by said sector format conversion device said (i)th first sector onto part or all of the (j)th second sector, wherein (j) is greater than or equal to 1 less than or equal to (M); transmitting said (j)th second sector to said data storage device; writing said (j)th second sector to said information storage medium; determining if a power failure warning has been received; operative if a power failure warning is received: prefetching the (j)+1th second sector; overlaying the (i)+1th first sector onto part of all of said (j)+1th second sector; saving said (j)+1th second sector; losing utility power to said information storage and retrieval system; restoring utility power to said information storage and retrieval system; destaging said (j)+1th second sector to said data storage device; and encoding said (j)+1th second sector to said information storage medium.