SEGMENTATION OF CACHE FOR PROVIDING SERVICE LEVEL TO BE CHANGED

摘要

PROBLEM TO BE SOLVED: To provide a mechanism for controlling a cache service to be provided to a host processor system connected to a storage device so that some host processors can receive higher cache performance than other host processors. SOLUTION: The system is provided with a process for accessing a 1st segment of a cache memory for an external host system of a 1st group connected to a storage device and process for accessing a 2nd segment of the cache memory for an external host system of a 2nd group connected to the storage device. At least part of the 2nd segment of the cache memory is not part of the 1st segment of the cache memory. The system may also be provided with a process for providing 1st data structure to the 1st segment of the cache memory and a process for providing 2nd data structure to the 2nd segment of the cache memory. The access of the 1st segment includes the access of the 1st data structure and the access of the 2nd segment includes the access of the 2nd data structure.