/share/man/man9/vm_page_dontneed.9

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  2. .\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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  29. .Dd July 30, 2001
    30. 

  30. .Dt VM_PAGE_DONTNEED 9
    31. 

  31. .Os
    32. 

  32. .Sh NAME
    33. 

  33. .Nm vm_page_dontneed
    34. 

  34. .Nd "indicate that a page is not needed anymore"
    35. 

  35. .Sh SYNOPSIS
    36. 

  36. .In sys/param.h
    37. 

  37. .In vm/vm.h
    38. 

  38. .In vm/vm_page.h
    39. 

  39. .Ft void
    40. 

  40. .Fn vm_page_dontneed "vm_page_t m"
    41. 

  41. .Sh DESCRIPTION
    42. 

  42. The
    43. 

  43. .Fn vm_page_dontneed
    44. 

  44. function advises the VM system that the given page is no longer
    45. 

  45. required.
    46. 

  46. If the page is already in the inactive queue or in the cache queue, this
    47. 

  47. function does nothing; otherwise the page is deactivated.
    48. 

  48. .Pp
    49. 

  49. Note that
    50. 

  50. .Fn vm_page_dontneed
    51. 

  51. does not necessarily deactivate a page, but instead implements an
    52. 

  52. algorithm that attempts to prevent small objects from having their
    53. 

  53. pages reused too quickly, and large objects from flushing smaller
    54. 

  54. ones from the queues as their pages are released.
    55. 

  55. .Sh SEE ALSO
    56. 

  56. .Xr vm_page_deactivate 9
    57. 

  57. .Sh AUTHORS
    58. 

  58. This manual page was written by
    59. 

  59. .An Chad David Aq davidc@acns.ab.ca .
    60.