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diff --git a/usr.sbin/iostat/iostat.8 b/usr.sbin/iostat/iostat.8 new file mode 100644 index 000000000000..11f0ef6fbeb6 --- /dev/null +++ b/usr.sbin/iostat/iostat.8 @@ -0,0 +1,546 @@ +.\" +.\" Copyright (c) 1997 Kenneth D. Merry. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. The name of the author may not be used to endorse or promote products +.\" derived from this software without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" Copyright (c) 1985, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.Dd November 26, 2023 +.Dt IOSTAT 8 +.Os +.Sh NAME +.Nm iostat +.Nd report +.Tn I/O +statistics +.Sh SYNOPSIS +.Nm +.Op Fl CdhIKoTxz +.Op Fl c Ar count +.Op Fl M Ar core +.Op Fl n Ar devs +.Op Fl N Ar system +.Oo +.Fl t +.Sm off +.Ar type , if , pass +.Sm on +.Oc +.Op Fl w Ar wait +.Op Ar drives +.Sh DESCRIPTION +The +.Nm +utility displays kernel +.Tn I/O +statistics on terminal, device and cpu operations. +The first statistics that are printed are averaged over the system uptime +(unless +.Fl I +is specified). +Any references to repetitions in this man page implicitly include the first +statistics output. +To get information about the current activity, a suitable wait time should +be specified, so that the subsequent sets of printed statistics will be +averaged over that time. +.Pp +The options are as follows: +.Bl -tag -width flag +.It Fl C +Display CPU statistics. +This is on by default, unless +.Fl d +or +.Fl x +is specified. +.It Fl c +Repeat the display +.Ar count +times. +If +.Fl c +is not specified and a wait interval is specified, +the default repeat count is infinity. +If no wait interval is specified, the default repeat count is 1. +.It Fl d +Display only device statistics. +If this flag is turned on, only device statistics will be displayed, unless +.Fl C +or +.Fl T +is also specified to enable the display of CPU or TTY statistics. +.It Fl h +Put +.Nm +in +.Sq top +mode. +In this mode, +.Nm +will show devices in order from highest to lowest bytes +per measurement cycle. +.It Fl I +Display total statistics for a given time period, rather than average +statistics for each second during that time period. +.It Fl K +In the old-style blocks transferred display +.Po Fl I +and +.Fl o Pc , +display block count in kilobytes rather than the device native block size. +.It Fl M +Extract values associated with the name list from the specified core +instead of the default +.Dq Pa /dev/kmem . +.It Fl N +Extract the name list from the specified system instead of the default +.Dq Pa /boot/kernel/kernel . +.It Fl n +Display up to +.Ar devs +number of devices. +The +.Nm +utility will display fewer devices if there are less than +.Ar devs +devices present. +.It Fl o +Display old-style +.Nm +device statistics. +Sectors per second, transfers per second, and milliseconds per seek are +displayed. +If +.Fl I +is specified, total blocks/sectors, total transfers, and +milliseconds per seek are displayed. +.It Fl T +Display TTY statistics. +This is on by default, unless +.Fl d +or +.Fl x +is specified. +.It Fl t +Specify which types of devices to display. +There are three different categories of devices: +.Pp +.Bl -tag -width indent -compact +.It device type: +.Bl -tag -width 9n -compact +.It da +Direct Access devices +.It sa +Sequential Access devices +.It printer +Printers +.It proc +Processor devices +.It worm +Write Once Read Multiple devices +.It cd +CD devices +.It scanner +Scanner devices +.It optical +Optical Memory devices +.It changer +Medium Changer devices +.It comm +Communication devices +.It array +Storage Array devices +.It enclosure +Enclosure Services devices +.It floppy +Floppy devices +.El +.Pp +.It interface: +.Bl -tag -width 9n -compact +.It IDE +Integrated Drive Electronics devices +.It SCSI +Small Computer System Interface devices +.It NVME +NVM Express Interface devices +.It other +Any other device interface +.El +.Pp +.It passthrough: +.Bl -tag -width 9n -compact +.It pass +Passthrough devices +.El +.El +.Pp +The user must specify at least one device type, and may specify at most +one device type from each category. +Multiple device types in a single device type statement must be separated by +commas and are ANDed together. +.Pp +Any number of +.Fl t +arguments may be specified on the command line. +All +.Fl t +arguments are ORed together to form a matching expression against which +all devices in the system are compared. +Any device that fully matches any +.Fl t +argument will be included in the +.Nm +output, up to the number of devices that can be displayed in +80 columns, or the maximum number of devices +.Pq Fl n +specified by the user. +.It Fl w +Pause +.Ar wait +seconds between each display. +If +.Fl w +is not specified, the default interval is 1 second. +.Pp +The +.Nm +command will accept and honor a non-integer number of seconds. +Note that the interval only has millisecond granularity. +Finer values will be truncated. +E.g., +.Dq Li -w1.0001 +is the same as +.Dq Li -w1.000 . +The interval will also suffer from modifications to +.Va kern.hz +so your mileage may vary. +.It Fl x +Show extended disk statistics. +Each disk is displayed on a line of its own with all available statistics. +If this flag is turned on, only disk statistics will be displayed, unless +.Fl C +or +.Fl T +is also specified to enable the display of CPU or TTY statistics. +.It Fl z +If +.Fl x +is specified, omit lines for devices with no activity. +.El +.Pp +The +.Nm +utility displays its information in the following format: +.Bl -tag -width flag +.It tty +.Bl -tag -width indent -compact +.It tin +characters read from terminals +.It tout +characters written to terminals +.El +.It devices +Device operations. +The header of the field is the device name and unit number. +The +.Nm +utility +will display as many devices as will fit in a standard 80 column screen, or +the maximum number of devices in the system, whichever is smaller. +If +.Fl n +is specified on the command line, +.Nm +will display the smaller of the +requested number of devices, and the maximum number of devices in the system. +To force +.Nm +to display specific drives, their names may be supplied on the command +line. +The +.Nm +utility +will not display more devices than will fit in an 80 column screen, unless +the +.Fl n +argument is given on the command line to specify a maximum number of +devices to display. +If fewer devices are specified on the command line than will fit in an 80 +column screen, +.Nm +will show only the specified devices. +.Pp +The standard +.Nm +device display shows the following statistics: +.Pp +.Bl -tag -width indent -compact +.It KB/t +kilobytes per transfer +.It tps +transfers per second +.It MB/s +megabytes per second +.El +.Pp +The standard +.Nm +device display, with the +.Fl I +flag specified, shows the following statistics: +.Pp +.Bl -tag -width indent -compact +.It KB/t +kilobytes per transfer +.It xfrs +total number of transfers +.It MB +total number of megabytes transferred +.El +.Pp +The extended +.Nm +device display, with the +.Fl x +flag specified, shows the following statistics: +.Pp +.Bl -tag -width indent -compact +.It r/s +read operations per second +.It w/s +write operations per second +.It kr/s +kilobytes read per second +.It kw/s +kilobytes write per second +.It qlen +transactions queue length +.It ms/r +average duration of read transactions, in milliseconds +.It ms/w +average duration of write transactions, in milliseconds +.It ms/o +average duration of all other transactions, in milliseconds +.It ms/t +average duration of all transactions, in milliseconds +.It %b +% of time the device had one or more outstanding transactions +.El +.Pp +The extended +.Nm +device display, with the +.Fl x +and +.Fl I +flags specified, shows the following statistics: +.Pp +.Bl -tag -width indent -compact +.It r/i +read operations per time period +.It w/i +write operations per time period +.It kr/i +kilobytes read per time period +.It kw/i +kilobytes write per time period +.It qlen +transactions queue length +.It tsvc_t/i +total duration of transactions per time period, in seconds +.It sb/i +total time the device had one or more outstanding transactions per +time period, in seconds +.El +.Pp +The old-style +.Nm +display (using +.Fl o ) +shows the following statistics: +.Pp +.Bl -tag -width indent -compact +.It sps +sectors transferred per second +.It tps +transfers per second +.It msps +average milliseconds per transaction +.El +.Pp +The old-style +.Nm +display, with the +.Fl I +flag specified, shows the following statistics: +.Pp +.Bl -tag -width indent -compact +.It blk +total blocks/sectors transferred +.It xfr +total transfers +.It msps +average milliseconds per transaction +.El +.It cpu +.Bl -tag -width indent -compact +.It \&us +% of cpu time in user mode +.It \&ni +% of cpu time in user mode running niced processes +.It \&sy +% of cpu time in system mode +.It \&in +% of cpu time in interrupt mode +.It \&id +% of cpu time in idle mode +.El +.El +.Sh FILES +.Bl -tag -width /boot/kernel/kernel -compact +.It Pa /boot/kernel/kernel +Default kernel namelist. +.It Pa /dev/kmem +Default memory file. +.El +.Sh EXAMPLES +.Dl iostat -w 1 da0 da1 cd0 +.Pp +Display statistics for the first two Direct Access devices and the first +CDROM device every second ad infinitum. +.Pp +.Dl iostat -c 2 +.Pp +Display the statistics for the first four devices in the system twice, with +a one second display interval. +.Pp +.Dl iostat -t da -t cd -w 1 +.Pp +Display statistics for all CDROM and Direct Access devices every second +ad infinitum. +.Pp +.Dl iostat -t da,scsi,pass -t cd,scsi,pass +.Pp +Display statistics once for all SCSI passthrough devices that provide access +to either Direct Access or CDROM devices. +.Pp +.Dl iostat -h -n 8 -w 1 +.Pp +Display up to 8 devices with the most I/O every second ad infinitum. +.Pp +.Dl iostat -dh -t da -w 1 +.Pp +Omit the TTY and CPU displays, show devices in order of performance and +show only Direct Access devices every second ad infinitum. +.Pp +.Dl iostat -Iw 3 +.Pp +Display total statistics every three seconds ad infinitum. +.Pp +.Dl iostat -odICTw 2 -c 9 +.Pp +Display total statistics using the old-style output format 9 times, with +a two second interval between each measurement/display. +The +.Fl d +flag generally disables the TTY and CPU displays, but since the +.Fl T +and +.Fl C +flags are given, the TTY and CPU displays will be displayed. +.Sh SEE ALSO +.Xr fstat 1 , +.Xr netstat 1 , +.Xr nfsstat 1 , +.Xr ps 1 , +.Xr systat 1 , +.Xr devstat 3 , +.Xr ctlstat 8 , +.Xr gstat 8 , +.Xr pstat 8 , +.Xr vmstat 8 +.Pp +The sections starting with ``Interpreting system activity'' in +.%T "Installing and Operating 4.3BSD" . +.Sh HISTORY +This version of +.Nm +first appeared in +.Fx 3.0 . +.Sh AUTHORS +.An Kenneth Merry Aq Mt ken@FreeBSD.org +.Sh BUGS +The use of +.Nm +as a debugging tool for crash dumps is probably limited because there is +currently no way to get statistics that only cover the time immediately before +the crash. +.Pp +Each +.Ar drives +argument is passed to +.Fn isdigit . +If +.Fn isdigit +returns true, +.Nm +switches into an undocumented traditional syntax and subsequent arguments, +if any, will not be interpreted as drive names. +This behavior collides with the one documented in this man page and prevents +specifying drive names starting with a number. +E.g., the following +.Bd -literal -offset indent +iostat ada0 ada1 2 3 cd0 +.Ed +.Pp +This document's use of +.Dq device type +is misleading. |