Patent ID: 7624228

Claim:
A method of controlling a cache memory in a disk drive, comprising: extracting a pattern of processing requests in which read requests making access to continuous areas in a logical block address (LBA) space on a disk repeatedly alternate with write requests making access to continuous or non-continuous areas in the LBA space; setting a position at which data about writing is started to be written to the cache memory, based on the ratio of the amount of data transferred to the cache memory during reading to the amount of data transferred to the cache memory during writing; executing cache control for the pattern of processing requests; making a decision as to whether the pattern of processing requests persists when a new processing request is received; making a decision as to whether data about writing has been just written to the disk if the pattern of processing requests persists; executing the cache control for the pattern of processing requests unless the data about writing has been just written to the disk; and resetting the position at which data about writing is started to be written to the cache memory if the data about writing has been just written to the disk.