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     DRUM(4)                                                   DRUM(4)

          drum - paging device

          This file refers to the paging device in use by the system.
          This may actually be a subdevice of one of the disk drivers,
          but in a system with paging spread across multiple disk
          drives or interleaved will be an indirect driver.


          Reads from the drum are not allowed across the interleaving
          boundaries.  Since these only occur every .5Mbytes or so,
          and since the system never allocates blocks across the
          boundary, this is usually not a problem.