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swapon, swapoff ? enable/disable devices and files for paging and swapping |
/sbin/swapon [?h ?V] |
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 |
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?V |
Display version |
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?s |
Display swap usage summary by device. This option is only available if /proc/swaps exists (probably not before kernel 2.1.25). |
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?a |
All devices marked as ‘‘sw’’ swap devices in /etc/fstab are made available. Devices that are already running as swap are silently skipped. |
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?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. |
You should not use swapon on a file with holes. Swap over NFS may not work. |
swapon(2), swapoff(2), fstab(5), init(8), mkswap(8), rc(8), mount(8) |
/dev/hd?? standard paging devices |
The swapon command appeared in 4.0BSD. |