Cache control system and method having hardware-based tag record allocation

1. Field of the Invention The present invention relates to a disk drive comprising a cache memory and a cache control system having a tag memory having a plurality of tag records, and means for allocating a tag record for responding to a host command. The cache memory has a plurality of sequentially-ordered memory clusters for caching disk data stored in sectors (not shown) on disks of a disk assembly . Conventionally the disk sectors are identified by logical block addresses (LBAs). The cache control system along with the tag memory and means for allocating tag records are embedded within the cache control system and thereby configured only for use in defining variable length segments of the memory clusters . The segments are defined without regard to the sequential order of the memory clusters