Patent Document ID: 8140788
Application ID: 11763340
Patent Flag: 1

Claim One:
1. An apparatus for selecting an input/output tape volume cache (TVC), the apparatus comprising: a memory device storing a computer readable program; a processor executing the computer readable program, the computer readable program comprising a history module maintaining access history instances for a plurality of clusters, each cluster comprising a TVC; a request module receiving an access request for a logical volume wherein an instance of the logical volume is stored on each of the plurality of clusters and each instance of the logical volume is synchronized with each other instance of the logical volume; an adjustment module weighting the access history instances in favor of recent access history instances; a calculation module calculating an affinity of the logical volume instance stored on each cluster of the plurality of clusters, wherein each affinity a is calculated as a = ∑ i = 1 n ⁢ k ( t 0 - t i ) where n is a number of access history instances, k is a constant, t 0 is a current time, and t i is a last read time stamp for access history instance i; and a selection module selecting a cluster TVC with a highest logical volume instance affinity as a TVC for the logical volume.