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SWAPON

NAME
SYNOPSIS
DESCRIPTION
NOTE
SEE ALSO
FILES
HISTORY

NAME

swapon, swapoff ? enable/disable devices and files for paging and swapping

SYNOPSIS

/sbin/swapon [?h ?V]
/sbin/swapon ?a [?v] [?e]
/sbin/swapon [?v] [?p
priority] specialfile ...
/sbin/swapon [?s]
/sbin/swapoff [?h ?V]
/sbin/swapoff ?a
/sbin/swapoff
specialfile ...

DESCRIPTION

Swapon is used to specify devices on which paging and swapping are to take place. Calls to swapon normally occur in the system multi-user initialization file /etc/rc making all swap devices available, so that the paging and swapping activity is interleaved across several devices and files.

Normally, the first form is used:

?h

Provide help

?V

Display version

?s

Display swap usage summary by device. This option is only available if /proc/swaps exists (probably not before kernel 2.1.25).

?a

All devices marked as ‘‘sw’’ swap devices in /etc/fstab are made available. Devices that are already running as swap are silently skipped.

?e

When ?a is used with swapon, ?e makes swapon silently skip devices that do not exist.

?p priority

Specify priority for swapon. This option is only available if swapon was compiled under and is used under a 1.3.2 or later kernel. priority is a value between 0 and 32767. See swapon(2) for a full description of swap priorities. Add pri=value to the option field of /etc/fstab for use with swapon -a.

Swapoff disables swapping on the specified devices and files, or on all swap entries in /etc/fstab when the ?a flag is given.

NOTE

You should not use swapon on a file with holes. Swap over NFS may not work.

SEE ALSO

swapon(2), swapoff(2), fstab(5), init(8), mkswap(8), rc(8), mount(8)

FILES

/dev/hd?? standard paging devices
/dev/sd??
standard (SCSI) paging devices
/etc/fstab
ascii filesystem description table

HISTORY

The swapon command appeared in 4.0BSD.


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