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dynamic_pager(8)          BSD System Manager's Manual         dynamic_pager(8)

     dynamic_pager -- external storage manager for dynamic pager

     dynamic_pager [-F filename] [-S filesize] [-H high-water-trigger] [-L low-water-trigger] [-P priority]

     The dynamic_pager daemon manages a pool of external swap files which the kernel uses to support demand
     paging.  This pool is expanded with new swap files as load on the system increases.  It is contracted
     when the swapping resources are no longer needed.  The dynamic_pager daemon also provides a notifica-tion notification
     tion service for those applications which wish to receive notices when the external paging pool expands
     or contracts.

     -F      The base name of the filename to use for the external paging files.  By default this is

     -H      If there are less than high-water-trigger bytes free in the external paging files, the kernel
             will signal dynamic_pager to add a new external paging file.

     -L      If there are more than low-water-trigger bytes free in the external paging files, the kernel
             will coalese in-use pages and signal dynamic_pager to discard an external paging file.
             Low-water-trigger must be greater than high-water-trigger + filesize.

     -P      This option is currently unimplemented.

     -S      The fixed filesize [in bytes] to use for the paging files.  By default dynamic_pager uses vari-able variable
             able sized paging files, using larger sized files as paging demands increase.  The -S, -H and
             -L options disable that default and cause dynamic_pager to use a series of fixed sized external
             paging files.

     /private/var/vm/swapfile*                           Default external paging files.
     /Library/Preferences/  Configuration file.

     The following keys can be specified in the configuration file.  Please see plist(5) for more informa-tion information
     tion about property list files.

     UseEncryptedSwap <boolean>
     This optional key activates encrypted swap (aka Secure VM), so that all data is encrypted before being
     written to a swap file.  The default is on for portable computers and off for other computers.

Mac OS X                         July 8, 2003                         Mac OS X

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