1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)drum.4 8.1 (Berkeley) 06/05/93 7.\" 8.Dd 9.Dt DRUM 4 10.Os BSD 4 11.Sh NAME 12.Nm drum 13.Nd paging device 14.Sh DESCRIPTION 15This file refers to the paging device in use by the system. 16This may actually be a subdevice of one of the disk drivers, but in 17a system with paging interleaved across multiple disk drives 18it provides an indirect driver for the multiple drives. 19.Sh FILES 20.Bl -tag -width /dev/drum 21.It Pa /dev/drum 22.El 23.Sh HISTORY 24The 25.Nm 26special file appeared in 27.Bx 3.0 . 28.Sh BUGS 29Reads from the drum are not allowed across the interleaving boundaries. 30Since these only occur every .5Mbytes 31or so, 32and since the system never allocates blocks across the boundary, 33this is usually not a problem. 34