NetBSD/usr.bin/vmstat/vmstat.8

217 lines
5.9 KiB
Groff

.\" $NetBSD: vmstat.8,v 1.14 1998/02/13 05:10:33 thorpej Exp $
.\"
.\" Copyright (c) 1986, 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. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. 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.
.\"
.\" @(#)vmstat.8 8.1 (Berkeley) 6/6/93
.\"
.TH VMSTAT 8 "February 12, 1998"
.UC 4
.SH NAME
vmstat \- report virtual memory statistics
.SH SYNOPSIS
.nf
.ft B
vmstat [ \-fHilmst ] [ \-h histname ] [ \-c count ] [ \-M core ]
.ti +5
[ \-N system ] [ \-w wait ] [ disks ]
.ft R
.fi
.SH DESCRIPTION
.I Vmstat
reports certain kernel statistics kept about process, virtual memory,
disk, trap and cpu activity.
.PP
The options are as follows:
.TP
\-c
Repeat the display
.I count
times.
The first display is for the time since a reboot and each subsequent report
is for the time period since the last display.
If no
.I wait
interval is specified, the default is 1 second.
.TP
\-f
Report fork statistics.
.TP
\-i
Report on the number of interrupts taken by each device since system
startup.
.TP
\-M
Extract values associated with the name list from the specified core
instead of the default ``/dev/mem''.
.TP
\-N
Extract the name list from the specified system instead of the default
``/netbsd''.
.TP
\-m
Report on the usage of kernel dynamic memory listed first by size of
allocation and then by type of usage.
.TP
\-s
Display the contents of the
.I sum
structure, giving the total number of several kinds of paging related
events which have occurred since system startup.
.TP
\-t
Report on the number of page in and page reclaims since system startup,
and the amount of time required by each.
.TP
\-w
Pause
.I wait
seconds between each display.
If no repeat
.I count
is specified, the default is infinity.
.PP
The following options only apply if
.I vmstat
was built with support for UVM:
.TP
\-l
List the UVM histories being maintained by the kernel.
.TP
\-h
Dump the specified UVM history.
.TP
\-H
Dump all UVM histories.
.PP
By default,
.I vmstat
displays the following information:
.PP
.TP
procs
Information about the numbers of processes in various states.
.sp
.RS
.nf
r in run queue
b blocked for resources (i/o, paging, etc.)
w runnable or short sleeper (< 20 secs) but swapped
.fi
.RE
.TP
memory
Information about the usage of virtual and real memory.
Virtual pages (reported in units of 1024 bytes) are considered active if
they belong to processes which are running or have run in the last 20
seconds.
.sp
.RS
.nf
avm active virtual pages
fre size of the free list
.fi
.RE
.TP
page
Information about page faults and paging activity.
These are averaged each five seconds, and given in units per second.
.sp
.RS
.nf
re page reclaims (simulating reference bits)
at pages attached (found in free list)
pi pages paged in
po pages paged out
fr pages freed per second
de anticipated short term memory shortfall
sr pages scanned by clock algorithm, per-second
.fi
.RE
.TP
disks
Disk transfers per second.
Typically paging will be split across the available drives.
The header of the field is the first character of the disk name and
the unit number.
If more than four disk drives are configured in the system,
.I vmstat
displays only the first four drives.
To force
.I vmstat
to display specific drives, their names may be supplied on the command line.
.TP
faults
Trap/interrupt rate averages per second over last 5 seconds.
.sp
.RS
.nf
in device interrupts per interval (including clock interrupts)
sy system calls per interval
cs cpu context switch rate (switches/interval)
.fi
.RE
.TP
cpu
Breakdown of percentage usage of CPU time.
.sp
.RS
.nf
us user time for normal and low priority processes
sy system time
id cpu idle
.fi
.RE
.SH EXAMPLES
The command ``vmstat -i 5'' will print what the system is doing every five
seconds; this is a good choice of printing interval since this is how often
some of the statistics are sampled in the system.
Others vary every second and running the output for a while will make it
apparent which are recomputed every second.
.SH FILES
.ta \w'/dev/mem 'u
/netbsd default kernel namelist
.br
/dev/mem default memory file
.SH SEE ALSO
.IR fstat (1),
.IR netstat (1),
.IR nfsstat (1),
.IR ps (1),
.IR systat (1),
.IR iostat (8),
.IR pstat (8)
.sp
The sections starting with ``Interpreting system activity'' in
.IR "Installing and Operating 4.3BSD" .
.SH BUGS
The \-c and \-w options are only available with the default output.