Patent attributes
Software that writes to storage disks using a differently sized sector format than that of the storage disks can require sector edges to be read from sectors of the disks before the write operation can occur. Write operations can consequently incur a performance penalty by having to pre-read sector edges. A sector-edge cache avoids this performance penalty by storing sector edges obtained from the sectors during previously executed read and write operations. Instead of having to pre-read a sector edge from disk during a write operation, an input/output controller can examine the sector-edge cache to determine if each appropriate sector edge is already present and then combine new data with that cached sector edge. RAID-5 implementations, which use a read-modify-write process to perform write operations, benefit from sector caches by reading and caching sector edges during the read phase so that no additional pre-reads are needed during the write phase.
