Patent ID: 7219256
Filing Date: 2007-05-15
Classification: G06F

Abstract:
1. A method for controlling data storage in a data storage system having a cache memory and a back end storage, said method comprising: in response to a detection of an event failure during an input/output (I/O) request from a host data processing system to said data storage system, determining whether or not there is an acknowledgement from said back end storage regarding the receipt of said data associated with said I/O request; and in response to a determination that there is an acknowledgement from said back end storage regarding the receipt of said data associated with said I/O request, in response to a determination that there is no acknowledgement from said back end storage regarding the receipt of said data associated with said I/O request, determining whether or not a retry operation needs to be performed; and in response to a determination that no retry operation is needed, notifying said host data processing system of said event failure.