Patent ID: 6567865
Filing Date: 2003-05-20
Classification: G06F

Abstract:
A storage system, comprising a control unit coupled to a plurality of host processors for receiving therefrom a plurality of input/output processing requests each containing a command designating an extent of the input/output processing request to thereby control data transfers between said host processors and a plurality of storage devices on the basis of the commands of said input/output processing requests, said control unit including memories for storing control information for said input/output processing requests on a request-by-request basis, said plurality of storage devices being coupled to said control unit, wherein logical devices are set up across said plurality of storage devices,wherein upon reception of a newly issued input/output processing request, said control unit stores the extent of said newly issued input/output processing request in said memory for executing said newly issued input/output processing request provided that any other input/output processing request whose extent overlaps with that of said newly issued input/output processing request is not resident in said memory, whereas when other input/output processing request whose extent overlaps with that of said newly issued input/output processing request is stored in said memory, information indicating that said newly issued input/output processing request is forced to wait for execution thereof is stored in said memory.