Patent ID: 6766414
Filing Date: 2004-07-20
Classification: G06F

Abstract:
A method for caching data in a data processing system including a host computer and a storage subsystem including at least one customer disk and a cache disk, said method comprising:receiving write transactions specifying data to be written to the at least one customer disk; caching said write transactions in a volatile memory of said storage subsystem; writing said cached write transactions to the cache disk, the cache disk divided into at least a first and second track, said writing step including: when transaction data is available, writing said transaction data sequentially to the first track of the cache disk; when transaction data is unavailable, writing padding data sequentially to the first track of the cache disk; in response to transaction data being unavailable, switching to the second track after reaching the end of the first track while writing padding data; in response to transaction data being unavailable, remaining on the second track, and continuously writing and overwriting padding data on the second track without moving to a subsequent track; and in response to transaction data becoming available, writing transaction data on the second track directly under an actuator head upon receiving the transaction data.