Patent ID: 6216179
Filing Date: 2001-04-10
Classification: G06F

Abstract:
A method of controlling at least one disk drive by using a plurality of channel processors and a plurality of drive processors, each of said plurality of channel processors and each of said plurality of drive processors having local memories, wherein any one of said channel processors and any one of said drive processors co-operatively process an input/output (I/O) request provided from a host computer with a first version of a program, said method comprising the steps of:processing an I/O request provided from the host computer by one of said plurality of channel processors and one of said plurality of drive processors which co-operatively operate with identical versions of the program, while transferring a second version of the program from a maintenance processor to one of said local memories; andprocessing an I/O request provided from the host computer by one of said plurality of channel processors and one of said plurality of drive processors which co-operatively process the I/O request provided by the host computer and which are operating with the second version of the program, after transferring the second version of the program provided from the maintenance processor to said plurality of channel processors and said plurality of drive processors.