Patent ID: 6230239
Filing Date: 2001-05-08
Classification: G06F

Abstract:
A method of controlling data migration in an information processing system which includes a CPU, a new storage system connected to said CPU and an old storage system connected to said new storage system, wherein data migration is conducted to transfer data from said old storage system to said new storage system, said method comprisingpermitting access to said storage systems by said CPU during data migration;determining whether said access is to a region where data migration has been completed;processing said access to said new storage system when said access is to a region where data migration has been completed; andprocessing said access to said old storage system and transferring data related to said access from said old storage system to said new storage system when said access is to a region where data migration has not been completedwherein said processing said access to said new storage system comprises:checking whether said access is a READ access or a WRITE access,when said access is a READ access, transferring data related to said access from said new storage system to said CPU, andwhen said access is a WRITE access, transferring data related to said access from said CPU to both said new storage system and said old storage system.