1.\" $NetBSD: iostat.8,v 1.12 1997/10/17 09:03:53 lukem Exp $ 2.\" 3.\" Copyright (c) 1985, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" from: @(#)iostat.8 8.1 (Berkeley) 6/6/93 35.\" 36.Dd Jan 18, 1996 37.Dt IOSTAT 8 38.Os NetBSD 1.1 39.Sh NAME 40.Nm iostat 41.Nd report 42.Tn I/O 43statistics 44.Sh SYNOPSIS 45.Nm 46.Op Fl CdDIT 47.Op Fl c Ar count 48.Op Fl M Ar core 49.Op Fl N Ar system 50.Op Fl w Ar wait 51.Op Ar drives 52.Sh DESCRIPTION 53.Nm 54displays kernel 55.Tn I/O 56statistics on terminal, disk and cpu operations. By default, 57.Nm 58displays one line of statistics averaged over the machine's run time. 59The use of 60.Fl c 61presents successive lines averaged over the 62.Ar wait 63period. 64The 65.Fl I 66option causes 67.Nm 68to print raw, unaveraged values. 69.Pp 70The options are as follows: 71.Bl -tag -width flag 72.It Fl c 73Repeat the display 74.Ar count 75times. 76Unless the 77.Fl I 78flag is in effect, the first display is for the time since a reboot and 79each subsequent report is for the time period since the last display. 80If no 81.Ar wait 82interval is specified, the default is 1 second. 83.It Fl C 84Show cpu statistics. This is enabled by default unless the 85.Fl d, 86.Fl D, 87or 88.Fl T 89flags are used. 90.It Fl d 91Show disk statistics. This is the default. Displays kilobytes per 92transfer, number of transfers, and megabytes transfered. Use of this 93flag disables display of cpu and tty statistics. 94.It Fl D 95Show alternative disk statistics. Displays kilobytes transfered, number of 96transfers, and time spent in transfers. Use of this flag disables the 97default display. 98.It Fl I 99Show the running total values, rather than an average. 100.It Fl M 101Extract values associated with the name list from the specified core 102instead of the default 103.Dq Pa /dev/mem . 104.It Fl N 105Extract the name list from the specified system instead of the default 106.Dq Pa /netbsd . 107.It Fl T 108Show tty statistics. This is enabled by default unless the 109.Fl C, 110.Fl d, 111or 112.Fl D 113flags are used. 114.It Fl w 115Pause 116.Ar wait 117seconds between each display. 118If no repeat 119.Ar count 120is specified, the default is infinity. 121.El 122.Pp 123.Nm 124displays its information in the following format: 125.Bl -tag -width flag 126.It tty 127.Bl -tag -width indent -compact 128.It tin 129characters read from terminals 130.It tout 131characters written to terminals 132.El 133.It disks 134Disk operations. 135The header of the field is the disk name and unit number. 136If more than four disk drives are configured in the system, 137.Nm 138displays only the first four drives. 139To force 140.Nm 141to display specific drives, their names may be supplied on the command 142line. 143.Pp 144.Bl -tag -width indent -compact 145.It KB/t 146Kilobytes transferred per disk transfer 147.It t/s 148transfers per second 149.It MB/s 150Megabytes transferred per second 151.Pp 152.El 153The alternative display format, (selected with 154.Fl D 155), presents the following values. 156.Bl -tag -width indent -compact 157.It KB 158Kilobytes transferred 159.It xfr 160Disk transfers 161.It time 162Seconds spent in disk activity 163.El 164.It cpu 165.Bl -tag -width indent -compact 166.It \&us 167% of cpu time in user mode 168.It \&ni 169% of cpu time in user mode running niced processes 170.It \&sy 171% of cpu time in system mode 172.It \&id 173% of cpu time in idle mode 174.El 175.El 176.Sh FILES 177.Bl -tag -width /dev/mem -compact 178.It Pa /netbsd 179Default kernel namelist. 180.It Pa /dev/mem 181Default memory file. 182.El 183.Sh SEE ALSO 184.Xr fstat 1 , 185.Xr netstat 1 , 186.Xr nfsstat 1 , 187.Xr \&ps 1 , 188.Xr systat 1 , 189.Xr pstat 8 , 190.Xr vmstat 8 191.Pp 192The sections starting with ``Interpreting system activity'' in 193.%T "Installing and Operating 4.3BSD" . 194