drum.4

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)drum.4	8.1	9/11/90
.\" SCCSID: @(#)drum.4	8.1	9/11/90
.TH drum 4
.SH Name
drum \- paging device
.SH Description
.NXR "drum keyword"
.NXR "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 interleaved across multiple disk drives,
it provides an indirect driver for the multiple drives.
.SH Restrictions
Reads from the drum are not allowed across the interleaving boundaries.
Because these occur only every
.BR . 5Mbytes
or so,
and because the system never allocates blocks across the boundary,
this is usually not a problem.
.SH Files
.PN /dev/drum
.SH See Also
MAKEDEV(8)