Patent ID: 6418510
Filing Date: 2002-07-09
Classification: G06F

Abstract:
A method for optimizing performance of a data storage system comprising a direct access storage device (DASD), a data cache, and a command queue of commands for accessing data stored on said DASD, said method comprising:a) receiving a data block; b) calculating a cost function C for not storing said data block in said data cache, wherein said cost function is given by C=(Tdâˆ’Tc)P, â€ƒwherein Td is an access time for accessing said data block in said DASD, Tc is an access time for accessing said data block in said data cache, and P is an access probability for said data block; c) calculating analogous cost functions for cached data blocks in said data cache; and d) replacing a selected cached data block with said data block, wherein said selected cached data block has a cost function that is lower than said cost function of said data block.