资料来源 : Free On-Line Dictionary of Computing

Group-Sweeping Scheduling
     
         (GSS) A disk scheduling strategy in which
        requests are served in cycles, in a round-robin manner.  To
        reduce disk arm movements ("{seek}ing"), the set of streams is
        divided into groups that are served in fixed order.  Streams
        within a group are served according to "{SCAN}".
     
        If all clients are assigned to one group, GSS reduces to SCAN,
        and if all clients are assigned to separate groups, GSS
        effectively becomes round-robin scheduling.  The service order
        within one group is not fixed, and a stream may in fact be
        first in one cycle while last in the next.  This variation has
        to be masked by extra buffering but whereas SCAN requires
        buffer space for all streams, GSS can reuse the buffer for
        each group and effect a trade-off between {seek optimisation}
        and buffer requirements.
     
        (1995-11-12)