Patent ID: 6611903
Filing Date: 2003-08-26
Classification: G06F

Abstract:
A storage subsystem including a first storage subsystem connected to a plurality of host computers via a first interface and a second storage subsystem connected to said first storage subsystem via a second interface so as to copy write data written in said first storage subsystem from said host computer onto said second storage subsystem from said first storage subsystem, thereby protecting the write data in said first and said second storage subsystems in a multiplex manner, said storage subsystem comprising:a storage control unit provided in said first storage subsystem and having a first threshold for controlling for each of said host computers an occupancy ratio of the write data whose copy to said second storage subsystem is incomplete in a data buffer in said first storage subsystem, and control logic for delaying the processing of a data write request from each of said host computers on the basis of said first threshold which is set for each of said host computers.