.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved. The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\" @(#)drum.4 4.1 (Berkeley) %G%
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.
Reads from the drum are not allowed across the interleaving boundaries.
Since these only occur every
and since the system never allocates blocks across the boundary,
this is usually not a problem.
projects / unix-history / blob