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Diffstat (limited to 'man2/swapon.2')
-rw-r--r-- | man2/swapon.2 | 202 |
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diff --git a/man2/swapon.2 b/man2/swapon.2 deleted file mode 100644 index 87bd6a0..0000000 --- a/man2/swapon.2 +++ /dev/null @@ -1,202 +0,0 @@ -.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992 -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt <michael@moria.de> -.\" Modified 1993-07-24 by Rik Faith <faith@cs.unc.edu> -.\" Modified 1995-07-22 by Michael Chastain <mec@duracef.shout.net> -.\" Modified 1995-07-23 by aeb -.\" Modified 1996-10-22 by Eric S. Raymond <esr@thyrsus.com> -.\" Modified 1998-09-08 by aeb -.\" Modified 2004-06-17 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" Modified 2004-10-10 by aeb -.\" 2004-12-14 mtk, Anand Kumria: added new errors -.\" 2007-06-22 Ivana Varekova <varekova@redhat.com>, mtk -.\" Update text describing limit on number of swap files. -.\" 2021-01-17 Alex Baranowski <alex@euro-linux.com> -.\" Update information about available swap files decreased by -.\" CONFIG_DEVICE_PRIVATE option. -.\" -.\" FIXME Linux 3.11 added SWAP_FLAG_DISCARD_ONCE and SWAP_FLAG_DISCARD_PAGES -.\" commit dcf6b7ddd7df8965727746f89c59229b23180e5a -.\" Author: Rafael Aquini <aquini@redhat.com> -.\" Date: Wed Jul 3 15:02:46 2013 -0700 -.\" -.TH swapon 2 2023-12-22 "Linux man-pages 6.7" -.SH NAME -swapon, swapoff \- start/stop swapping to file/device -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <sys/swap.h> -.P -.BI "int swapon(const char *" path ", int " swapflags ); -.BI "int swapoff(const char *" path ); -.fi -.SH DESCRIPTION -.BR swapon () -sets the swap area to the file or block device specified by -.IR path . -.BR swapoff () -stops swapping to the file or block device specified by -.IR path . -.P -If the -.B SWAP_FLAG_PREFER -flag is specified in the -.BR swapon () -.I swapflags -argument, the new swap area will have a higher priority than default. -The priority is encoded within -.I swapflags -as: -.P -.in +4n -.EX -.I "(prio << SWAP_FLAG_PRIO_SHIFT) & SWAP_FLAG_PRIO_MASK" -.EE -.in -.P -If the -.B SWAP_FLAG_DISCARD -flag is specified in the -.BR swapon () -.I swapflags -argument, freed swap pages will be discarded before they are reused, -if the swap device supports the discard or trim operation. -(This may improve performance on some Solid State Devices, -but often it does not.) -See also NOTES. -.P -These functions may be used only by a privileged process (one having the -.B CAP_SYS_ADMIN -capability). -.SS Priority -Each swap area has a priority, either high or low. -The default priority is low. -Within the low-priority areas, -newer areas are even lower priority than older areas. -.P -All priorities set with -.I swapflags -are high-priority, higher than default. -They may have any nonnegative value chosen by the caller. -Higher numbers mean higher priority. -.P -Swap pages are allocated from areas in priority order, -highest priority first. -For areas with different priorities, -a higher-priority area is exhausted before using a lower-priority area. -If two or more areas have the same priority, -and it is the highest priority available, -pages are allocated on a round-robin basis between them. -.P -As of Linux 1.3.6, the kernel usually follows these rules, -but there are exceptions. -.SH RETURN VALUE -On success, zero is returned. -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B EBUSY -(for -.BR swapon ()) -The specified -.I path -is already being used as a swap area. -.TP -.B EINVAL -The file -.I path -exists, but refers neither to a regular file nor to a block device; -.TP -.B EINVAL -.RB ( swapon ()) -The indicated path does not contain a valid swap signature or -resides on an in-memory filesystem such as -.BR tmpfs (5). -.TP -.BR EINVAL " (since Linux 3.4)" -.RB ( swapon ()) -An invalid flag value was specified in -.IR swapflags . -.TP -.B EINVAL -.RB ( swapoff ()) -.I path -is not currently a swap area. -.TP -.B ENFILE -The system-wide limit on the total number of open files has been reached. -.TP -.B ENOENT -The file -.I path -does not exist. -.TP -.B ENOMEM -The system has insufficient memory to start swapping. -.TP -.B EPERM -The caller does not have the -.B CAP_SYS_ADMIN -capability. -Alternatively, the maximum number of swap files are already in use; -see NOTES below. -.SH STANDARDS -Linux. -.SH HISTORY -The -.I swapflags -argument was introduced in Linux 1.3.2. -.SH NOTES -The partition or path must be prepared with -.BR mkswap (8). -.P -There is an upper limit on the number of swap files that may be used, -defined by the kernel constant -.BR MAX_SWAPFILES . -Before Linux 2.4.10, -.B MAX_SWAPFILES -has the value 8; -since Linux 2.4.10, it has the value 32. -Since Linux 2.6.18, the limit is decreased by 2 (thus 30), -since Linux 5.19, the limit is decreased by 3 (thus: 29) -if the kernel is built with the -.B CONFIG_MIGRATION -option -(which reserves two swap table entries for the page migration features of -.BR mbind (2) -and -.BR migrate_pages (2)). -Since Linux 2.6.32, the limit is further decreased by 1 -if the kernel is built with the -.B CONFIG_MEMORY_FAILURE -option. -Since Linux 5.14, the limit is further decreased by 4 -if the kernel is built with the -.B CONFIG_DEVICE_PRIVATE -option. -Since Linux 5.19, the limit is further decreased by 1 -if the kernel is built with the -.B CONFIG_PTE_MARKER -option. -.P -Discard of swap pages was introduced in Linux 2.6.29, -then made conditional -on the -.B SWAP_FLAG_DISCARD -flag in Linux 2.6.36, -.\" To be precise: 2.6.35.5 -which still discards the -entire swap area when -.BR swapon () -is called, even if that flag bit is not set. -.SH SEE ALSO -.BR mkswap (8), -.BR swapoff (8), -.BR swapon (8) |