/share/man/man9/vm_page_dontneed.9

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29.Dd July 30, 2001
30.Dt VM_PAGE_DONTNEED 9
31.Os
32.Sh NAME
33.Nm vm_page_dontneed
34.Nd "indicate that a page is not needed anymore"
35.Sh SYNOPSIS
36.In sys/param.h
37.In vm/vm.h
38.In vm/vm_page.h
39.Ft void
40.Fn vm_page_dontneed "vm_page_t m"
41.Sh DESCRIPTION
42The
43.Fn vm_page_dontneed
44function advises the VM system that the given page is no longer
45required.
46If the page is already in the inactive queue or in the cache queue, this
47function does nothing; otherwise the page is deactivated.
48.Pp
49Note that
50.Fn vm_page_dontneed
51does not necessarily deactivate a page, but instead implements an
52algorithm that attempts to prevent small objects from having their
53pages reused too quickly, and large objects from flushing smaller
54ones from the queues as their pages are released.
55.Sh SEE ALSO
56.Xr vm_page_deactivate 9
57.Sh AUTHORS
58This manual page was written by
59.An Chad David Aq davidc@acns.ab.ca .