swap(8) 맨 페이지 - 윈디하나의 솔라나라

개요

섹션
맨 페이지 이름
검색(S)

swap(8)

swap(8)                 System Administration Commands                 swap(8)

NAME
       swap - swap administrative interface

SYNOPSIS
       /usr/sbin/swap -a [-t] swapname [swaplow] [swaplen]


       /usr/sbin/swap -d [-t] swapname [swaplow]


       /usr/sbin/swap -l [-h | -k | --scale[=item1,item2,...]]


       /usr/sbin/swap -s [-h | --scale[=item1,item2,...]]

DESCRIPTION
       The  swap utility provides a method of adding, deleting, and monitoring
       the system swap areas used by the memory manager.

OPTIONS
       The following options are supported:

       -a [-t] swapname [swaplow] [swaplen]

           Add the specified swap area. This option can only be used by an ad‐
           ministrator who is assigned the File System Management rights  pro‐
           file  or  by root. swapname is the name of the swap area or regular
           file. On a system running a ZFS file system, specify a ZFS  volume,
           such  as  rpool/swap,  for  a swap area. Unless the -t is given the
           change will persist across reboots. Using a regular file  for  swap
           is not supported on a ZFS file system.

           swaplow  is  the  offset in 512-byte blocks into the file where the
           swap area should begin. swaplen is the desired length of  the  swap
           area  in 512-byte blocks. The value of swaplen can not be less than
           16. For example, if n blocks are specified, then (n-1) blocks would
           be the actual swap length. swaplen must be at  least  one  page  in
           length. The size of a page of memory can be determined by using the
           pagesize  command.  See  pagesize(1). If the swap file is not a ZFS
           volume or lofi device the first page of a swap  file  is  automati‐
           cally  skipped, and as a swap file needs to be at least one page in
           length, the minimum size should be a multiple of 2 pagesize  bytes.
           The size of a page of memory is machine-dependent.

           swaplow  +  swaplen  must  be less than or equal to the size of the
           swap file. If swaplen is not  specified,  an  area  will  be  added
           starting  at  swaplow  and  extending  to the end of the designated
           file. If neither swaplow nor swaplen are specified, the whole  file
           or  device  will be used. For swap files that are not ZFS volume or
           lofi devices the first page is skipped to protect  any  label  that
           might be present.

           Swap  areas  are  added  automatically during system startup by the
           svc:/system/swap service. This service adds all  swap  areas  which
           have  not  been  added  with  the  -t  flag or are specified in the
           /etc/vfstab file. For the syntax of these specifications,  see  vf‐
           stab(5) man page.

           ZFS  volumes used as a swap device will always be encrypted regard‐
           less of the value of the encryption property for  the  ZFS  volume.
           See zfs_encrypt(8).

           To  use an NFS or local file system swapname, you should first cre‐
           ate a file using mkfile(8). A local file system swap file  can  now
           be  added  to  the running system by just running the swap  -a com‐
           mand. For NFS mounted swap files, the server needs  to  export  the
           file. Do this by performing the following steps:

               1.     Run this on NFS server:

                        share -F nfs -o  \
                        rw=clientname,root=clientname directory-with-swap-file



               2.     Have the client add the following lines to /etc/vfstab:

                        server:directory-with-swap-file -
                        local-path-to-directory nfs    -   yes   -
                        local-path-to-directory/swap-file -  -
                        swap   - no    -



               3.     Enable NFS client service on the client:

                        svcadm enable nfs/client



               4.     Reboot the client.




       -d swapname

           Delete  the specified swap area. This option can only be used by an
           administrator who is assigned the  File  System  Management  rights
           profile  or by root. swapname is the name of the swap file: for ex‐
           ample, /dev/dsk/c0t0d0s1 or a regular file. swaplow is  the  offset
           in  512-byte blocks into the swap area to be deleted. If swaplow is
           not specified, the area will be  deleted  starting  at  the  second
           page.  When the command completes, swap blocks can no longer be al‐
           located from this area and all swap blocks  previously  in  use  in
           this swap area have been moved to other swap areas.

           If  the  swap  area was a ZFS volume that was not added with the -t
           flag the kvol_swap  ZFS property is set to off unless the  -t  flag
           is given.


       -h

           All  sizes  are scaled to a human readable format. The -h option is
           equivalent to using the --scale=max,1024 option.


       -k

           Write the files sizes in units of 1024 bytes.


       -l

           List the status of  all  the  swap  areas.  The  output  has  these
           columns:


           path

               The path name for the swap area.


           dev

               The  major/minor device number in decimal if it is a block spe‐
               cial device; zeroes otherwise.


           swaplo

               The swaplow value for the area in 512-byte blocks.


           blocks

               The swaplen value for the area in 512-byte blocks.


           free

               The number of 512-byte blocks in this area that  are  not  cur‐
               rently allocated.


           encrypted

               Shows yes if the device is encrypted and no otherwise.

           The list does not include swap space in the form of physical memory
           because this space is not associated with a particular swap area.

           If  swap   -l  is  run  while  swapname  is in the process of being
           deleted (by swap  -d), the string INDEL will appear  in  a  seventh
           column of the swap stats.


       -s

           Print  summary  information about total swap space usage and avail‐
           ability:


           allocated

               The total amount of swap space in bytes currently allocated for
               use as backing store.


           reserved

               The total amount of swap space in  bytes  not  currently  allo‐
               cated, but claimed by memory mappings for possible future use.


           used

               The  total  amount  of swap space in bytes that is either allo‐
               cated or reserved.


           available

               The total swap space in bytes that is currently  available  for
               future reservation and allocation.

           These  numbers include swap space from all configured swap areas as
           listed by the -l option, as well as swap space in the form of phys‐
           ical memory.


       --scale[=item1,item2,...]

           All sizes are scaled to a human readable format. Scaling is done by
           repetitively dividing by 1024, unless otherwise specified.  --scale
           specified  without  arguments enables default scaled output, and is
           equivalent to --scale=max,1024. See scale(7)  for  a  complete  de‐
           scription of --scale features.


       -t

           When  adding or removing a ZFS swap volume do not set the kvol_swap
           property so the change will not persist across reboot.


USAGE
       A block device larger than 2 Gbytes can be fully utilized for  swap  up
       to 2^63 −1 bytes.

ENVIRONMENT VARIABLES
       See  environ(7) for descriptions of the following environment variables
       that affect the execution of swap: LC_CTYPE and LC_MESSAGE.

ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:

       tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE  TYPEAT‐
       TRIBUTE VALUE _ Availabilitysystem/core-os


SEE ALSO
       pagesize(1),  getpagesize(3C),  vfstab(5), attributes(7), scale(7), mk‐
       file(8), shareall(8), zfs(8), zfs_encrypt(8)

NOTES
       For information about setting up a swap area with  ZFS,  see  the  book
       Managing ZFS File Systems in Oracle Solaris 11.4.

WARNINGS
       No  check is done to determine if a swap area being added overlaps with
       an existing file system.

HISTORY
       Support for the --scale option was added to the swap command in  Oracle
       Solaris 11.4.30.


       The encrypted column was added to the output of the -l option in Oracle
       Solaris 11.4.24.


       The  -h and -k options were added to the swap command in Oracle Solaris
       11.0, thanks to a  contribution  by  Yann  Poupet  to  the  OpenSolaris
       project.


       The  swap command; with support for the -a, -d, -l, and -s options; was
       added to Solaris in the Solaris 2.0 release, replacing the swapon  com‐
       mand used in SunOS 4.

Oracle Solaris 11.4            25 February 2023                        swap(8)
맨 페이지 내용의 저작권은 맨 페이지 작성자에게 있습니다.
RSS ATOM XHTML 5 CSS3