DISK SUBSYSTEM AND METHOD FOR CONTROLLING MEMORY ACCESS

摘要

In a prior art disk subsystem formed by duplicating a shared memory (SM) in a DRAM (first area) and a SRAM (second area) having a higher speed than the DRAM, the data stored in the SRAM cannot be switched collectively while maintaining access to the SM, so that the access performance was deteriorated. According to the present invention, when there is a change in setting of data stored in a second area (SRAM), a data corresponding to the setting after the change is stored from a first area (DRAM) of a slave surface side SM to the second area (SRAM), and the setting of data of the second area (SRAM) is changed. After changing the setting, the slave surface side SM is changed to a master surface side SM.