A system and associated method efficiently complete write commands in an ISF
disk
drive/RAID system with minimal disk accesses to the underlying disk drives. The
system updates data in a parity-based disk array system by receiving a write command
to write new data. The present system minimizes the number of disk accesses. The
present system completes the same or comparable write commands in a total of four
accesses to the disk drives. This is realized by combining the read-modify-write
operation of updating one or more sectors in an ISF cluster with the read-modify-write
operation associated with updating one or more sectors in a parity-based array
system, such as a RAID-5 system.
