<storage, algorithm> (GSS) A disk scheduling strategy in which
requests are served in cycles, in a round-robin manner. To
reduce disk arm movements ("seeking"), 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)
Nearby terms:
Group Code Recording « group identifier « Group Separator « Group-Sweeping Scheduling » Groupware » Groupwise » grovel
