1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as 9.\" the first lines of this file unmodified other than the possible 10.\" addition of one or more copyright notices. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice(s), this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY 16.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18.\" DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" 27.Dd July 30, 2001 28.Dt VM_PAGE_DONTNEED 9 29.Os 30.Sh NAME 31.Nm vm_page_dontneed 32.Nd "indicate that a page is not needed anymore" 33.Sh SYNOPSIS 34.In sys/param.h 35.In vm/vm.h 36.In vm/vm_page.h 37.Ft void 38.Fn vm_page_dontneed "vm_page_t m" 39.Sh DESCRIPTION 40The 41.Fn vm_page_dontneed 42function advises the VM system that the given page is no longer 43required. 44If the page is already in the inactive queue or in the cache queue, this 45function does nothing; otherwise the page is deactivated. 46.Pp 47Note that 48.Fn vm_page_dontneed 49does not necessarily deactivate a page, but instead implements an 50algorithm that attempts to prevent small objects from having their 51pages reused too quickly, and large objects from flushing smaller 52ones from the queues as their pages are released. 53.Sh SEE ALSO 54.Xr vm_page_deactivate 9 55.Sh AUTHORS 56This manual page was written by 57.An Chad David Aq Mt davidc@acns.ab.ca . 58