1.\" Copyright (c) 1989, 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. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" From: @(#)nfsiod.8 8.2 (Berkeley) 2/22/94 29.\" $FreeBSD$ 30.\" 31.Dd December 26, 2009 32.Dt NFSIOD 8 33.Os 34.Sh NAME 35.Nm nfsiod 36.Nd local 37.Tn NFS 38asynchronous I/O server 39.Sh SYNOPSIS 40.Nm 41.Op Fl n Ar num_servers 42.Sh DESCRIPTION 43The 44.Nm 45utility controls the maximum number of 46.Nm 47kernel processes which run on an 48.Tn NFS 49client machine to service asynchronous I/O requests to its server. 50Having 51.Nm 52kernel processes 53improves performance but is not required for correct operation. 54.Pp 55The option is as follows: 56.Bl -tag -width indent 57.It Fl n 58Specify how many processes are permitted to be started. 59.El 60.Pp 61Without an option, 62.Nm 63displays the current settings. 64A client should allow enough number of processes to handle its maximum 65level of concurrency, typically four to six. 66.Pp 67If 68.Nm 69detects that the running kernel does not include 70.Tn NFS 71support, it will attempt to load a kernel module containing 72.Tn NFS 73code, using 74.Xr kldload 2 . 75If this fails, or no 76.Tn NFS 77module was available, 78.Nm 79exits with an error. 80.Sh EXIT STATUS 81.Ex -std 82.Sh SEE ALSO 83.Xr nfsstat 1 , 84.Xr kldload 2 , 85.Xr nfssvc 2 , 86.Xr mountd 8 , 87.Xr nfsd 8 , 88.Xr rpcbind 8 89.Sh HISTORY 90The 91.Nm 92utility first appeared in 93.Bx 4.4 . 94.Pp 95Starting with 96.Fx 5.0 , 97the utility no longer starts daemons, but only serves as a vfs 98loader and 99.Xr sysctl 3 100wrapper. 101