/LEVEL={n}
       /LEVEL=2 (default)

          The defragmentation process selects files for
          defragmentation (from among those not excluded) based
          on the /LEVEL qualifier. Once a file is selected as
          a candidate, the defragmentation process attempts
          to fully defragment that file (make it 100 percent
          contiguous). Specify the level number as an integer
          ranging from 1 to 5:

          o  /LEVEL=1

             Any file that is not 100 percent contiguous, or
             can be selected using levels 2-4, is a candidate
             for defragmentation.

          o  /LEVEL=2 (default)

             Any file whose extents cannot be completely
             mapped by the mapping window, or that can be
             selected using levels 3 or 4, is a candidate for
             defragmentation. The default window value is 7 and
             can be set for a given volume using:

              $ SET VOLUME {device-spec}/WINDOWS=[n]

          o  /LEVEL=3

             Any file with retrieval pointers in more than one
             file header, or that can be selected using level
             4, is a candidate for defragmentation.

          o  /LEVEL=4

             The defragmentation process for level 4 processing
             performs only free space consolidation. This level
             is used in conjunction with the /CONSOLIDATE_
             FREESPACE qualifier.

          o  /LEVEL=5

             This level requests a volume analysis only;
             no defragmentation occurs. The statistical
             results are available in the log file, which is
             required when /LEVEL=5 is selected (see the /LOG
             qualifier). If level 5 is selected, the /LEVEL=2
             candidate file specifications are listed in the
             full log file.