within a library each of the accessors is assigned a given zone of primary access wherein each of the zones of primary access has at least one boundary accessor usage is calculated by adding a score for each access to total accesses for each accessor the totals are evaluated to determine that one or more of the boundaries requires adjustment and the boundaries are adjusted in accordance with the evaluation by changing the average span of each accessor dynamically the method can equalize the use of each accessor minimizing library latency application_number US 38595099 A description with reference now to the figures and in particular with reference to fig1 one embodiment of a library access system is depicted in accordance with the present invention the library access system comprises a media storage 14 which contains frames 26 which contain columns 25 for the storage of media such as tapes optical or magnetic disks and other storage media columns 25 contain individual cells for each media item disposed along the axis perpendicular to rail 12 the frames 26 may also contain drives for reading and writing the media accessors 16 and 18 move along a rail 12 positioned such that they can remove and replace media from the columns 25 in a frame 26 control connections 28 which may be flexible harnesses may be replaced by other suitable means such as an infrared or radio communications links drive 17 and 19 are positioned so that accessors 16 and 18 can insert or remove media controller 20 provides control signals for moving and operating accessors 16 and 18 the controller.