Patent ID: 6269423
Filing Date: 2001-07-31
Classification: G06F,Y10S

Abstract:
A method for improving caching in a virtual tape system, comprising the steps of:correlating logical volume usage to externally determined file characteristics to derive a usage history for cached logical volumes; wherein the step of correlating further comprises the steps of:associating the first logical volume with a logical volume type based on predefined characteristics;assigning a time bin for the type of the first logical volume based on the time of last access of the first logical volume therein, the time of current access of the first logical volume and based on the type assigned to the first logical volume at the time the first logical volume was last accessed; andupdating a usage count in the time bin for the type;maintaining a record of the usage history in time bins; andmanaging the migration of the logical volumes according to the usage history and the externally determined file characteristics of the logical volume.