A data archiving controller automatically determines a whether a main
storage devices has usage ratio in excess of a maximum limit and if an
archiving or backing storage device has sufficient directory space to
accept files from the main storage devices. The data archiving controller
then determines using fuzzy logic the number of files to be transferred
from the main storage devices to the backing storage devices. The data
archiving controller has a set allocating apparatus in communication with
the main storage device and the backing storage devices to receive
retention device usage parameters for classification within
classification sets. A membership rules retaining device contains the
classification parameter defining rules by which the retention device
usage parameters are assigned to the classification sets. The archiving
controller has a rule evaluation apparatus for determining a quantity of
data to be archived. The quantity of data to be archived is based on
evaluation rules determined by the classification sets. A data
designation apparatus designates the number of files to be archived and
then designates the files to be transferred between the main storage
device and backing storage devices.