a4671335c5
The original commit added granularity to the transaction latency display in the extended device stats mode, but didn't update the man page. Reported by: Miroslav Lachman <000.fbsd@quip.cz> via jmg MFC after: 1 day
523 lines
13 KiB
Groff
523 lines
13 KiB
Groff
.\"
|
|
.\" 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.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.\" 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.
|
|
.\"
|
|
.\" @(#)iostat.8 8.1 (Berkeley) 6/6/93
|
|
.\"
|
|
.Dd May 22, 2015
|
|
.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.
|
|
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
|
|
Repeat the display
|
|
.Ar count
|
|
times.
|
|
If no repeat
|
|
.Ar count
|
|
is specified, the default depends on whether
|
|
.Fl w
|
|
is specified.
|
|
With
|
|
.Fl w
|
|
the default repeat count is infinity, otherwise it is 1.
|
|
.It Fl C
|
|
Display CPU statistics.
|
|
This is on by default, unless
|
|
.Fl d
|
|
or
|
|
.Fl x
|
|
is specified.
|
|
.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 blocks transferred display (-o), display block count in kilobytes rather
|
|
then 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
|
|
Display up to
|
|
.Ar devs
|
|
number of devices.
|
|
The
|
|
.Nm
|
|
utility will display fewer devices if there are not
|
|
.Ar devs
|
|
devices present.
|
|
.It Fl N
|
|
Extract the name list from the specified system instead of the default
|
|
.Dq Pa /boot/kernel/kernel .
|
|
.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
|
|
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 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.
|
|
.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 specified by the user.
|
|
.It Fl T
|
|
Display TTY statistics.
|
|
This is on by default, unless
|
|
.Fl d
|
|
or
|
|
.Fl x
|
|
is specified.
|
|
.It Fl w
|
|
Pause
|
|
.Ar wait
|
|
seconds between each display.
|
|
If no
|
|
.Ar wait
|
|
interval is specified, the default 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.
|
|
.It Fl ?\&
|
|
Display a usage statement and exit.
|
|
.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.
|