mmap.2 (128411) | mmap.2 (131504) |
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1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. 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, this list of conditions and the following disclaimer. --- 16 unchanged lines hidden (view full) --- 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)mmap.2 8.4 (Berkeley) 5/11/95 | 1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. 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, this list of conditions and the following disclaimer. --- 16 unchanged lines hidden (view full) --- 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)mmap.2 8.4 (Berkeley) 5/11/95 |
33.\" $FreeBSD: head/lib/libc/sys/mmap.2 128411 2004-04-18 23:36:45Z cperciva $ | 33.\" $FreeBSD: head/lib/libc/sys/mmap.2 131504 2004-07-02 23:52:20Z ru $ |
34.\" 35.Dd November 17, 2001 36.Dt MMAP 2 37.Os 38.Sh NAME 39.Nm mmap 40.Nd allocate memory, or map files or devices into memory 41.Sh LIBRARY --- 134 unchanged lines hidden (view full) --- 176It is recommended that you create the backing store by 177.Fn write Ns ing 178zero's to the backing file rather than 179.Fn ftruncate Ns ing 180it. 181You can test file fragmentation by observing the KB/t (kilobytes per 182transfer) results from an 183.Dq Li iostat 1 | 34.\" 35.Dd November 17, 2001 36.Dt MMAP 2 37.Os 38.Sh NAME 39.Nm mmap 40.Nd allocate memory, or map files or devices into memory 41.Sh LIBRARY --- 134 unchanged lines hidden (view full) --- 176It is recommended that you create the backing store by 177.Fn write Ns ing 178zero's to the backing file rather than 179.Fn ftruncate Ns ing 180it. 181You can test file fragmentation by observing the KB/t (kilobytes per 182transfer) results from an 183.Dq Li iostat 1 |
184while reading a large file sequentially, e.g. using | 184while reading a large file sequentially, e.g.\& using |
185.Dq Li dd if=filename of=/dev/null bs=32k . 186.Pp 187The 188.Xr fsync 2 189system call will flush all dirty data and metadata associated with a file, 190including dirty NOSYNC VM data, to physical media. 191The 192.Xr sync 8 --- 180 unchanged lines hidden --- | 185.Dq Li dd if=filename of=/dev/null bs=32k . 186.Pp 187The 188.Xr fsync 2 189system call will flush all dirty data and metadata associated with a file, 190including dirty NOSYNC VM data, to physical media. 191The 192.Xr sync 8 --- 180 unchanged lines hidden --- |