1.\" $NetBSD: vmstat.1,v 1.26 2022/02/09 07:34:08 mrg Exp $ 2.\" 3.\" Copyright (c) 2000, 2007 The NetBSD Foundation, Inc. 4.\" 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.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 16.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25.\" POSSIBILITY OF SUCH DAMAGE. 26.\" 27.\" Copyright (c) 1986, 1993 28.\" The Regents of the University of California. All rights reserved. 29.\" 30.\" Redistribution and use in source and binary forms, with or without 31.\" modification, are permitted provided that the following conditions 32.\" are met: 33.\" 1. Redistributions of source code must retain the above copyright 34.\" notice, this list of conditions and the following disclaimer. 35.\" 2. Redistributions in binary form must reproduce the above copyright 36.\" notice, this list of conditions and the following disclaimer in the 37.\" documentation and/or other materials provided with the distribution. 38.\" 3. Neither the name of the University nor the names of its contributors 39.\" may be used to endorse or promote products derived from this software 40.\" without specific prior written permission. 41.\" 42.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 43.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 44.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 45.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 46.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 47.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 48.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 49.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 50.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 51.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 52.\" SUCH DAMAGE. 53.\" 54.\" @(#)vmstat.8 8.1 (Berkeley) 6/6/93 55.\" 56.Dd February 1, 2022 57.Dt VMSTAT 1 58.Os 59.Sh NAME 60.Nm vmstat 61.Nd report virtual memory statistics 62.Sh SYNOPSIS 63.Nm 64.Op Fl CefHiLlmstUvW 65.Op Fl c Ar count 66.Op Fl h Ar hashname 67.Op Fl M Ar core 68.Op Fl N Ar system 69.Op Fl n Ar diskcount 70.Op Fl u Ar histname 71.Op Fl w Ar wait 72.Op Ar disks 73.Sh DESCRIPTION 74.Nm 75reports certain kernel statistics kept about process, virtual memory, 76disk, trap, and CPU activity. 77If 78.Nm 79is invoked without any options, it displays the summary of statistics since 80boot and exits. 81This is also referred to as the first line of 82.Nm . 83.Pp 84The options are as follows: 85.Bl -tag -width xxxhistname 86.It Fl C 87Report on kernel memory caches. 88Combine with the 89.Fl m 90option to see information about memory pools that back the caches. 91.It Fl c Ar count 92Repeat the display 93.Ar count 94times. 95The first display is for the time since a reboot and each subsequent report 96is for the time period since the last display. 97If no 98.Ar wait 99interval is specified, the default is 1 second. 100.It Fl e 101Report the values of system event counters. 102.It Fl f 103Report fork statistics. 104.It Fl H 105Report all hash table statistics. 106.It Fl h Ar hashname 107Report hash table statistics for 108.Ar hashname . 109.It Fl i 110Report the values of system interrupt counters. 111.It Fl L 112List all the hashes supported for 113.Fl h 114and 115.Fl H . 116.It Fl l 117List the UVM histories being maintained by the kernel. 118.It Fl M Ar core 119Extract values associated with the name list from the specified core 120instead of the default 121.Pa /dev/mem . 122.It Fl m 123Report on the list of the kernel memory pools and their usage. 124.It Fl N Ar system 125Extract the name list from the specified system instead of the default 126.Pa /netbsd . 127.It Fl n Ar diskcount 128Display up to 129.Ar diskcount 130disks in the standard output, instead of the default 2. 131.It Fl s 132Display the contents of the 133.Dv uvmexp 134structure. 135This contains various paging event and memory status counters. 136.It Fl t 137Display the contents of the 138.Dv vmtotal 139structure. 140This includes information about processes and virtual memory. 141.Pp 142The process part shows the number of processes in the following states: 143.Pp 144.Bl -tag -width abc -compact 145.It ru 146on the run queue 147.It dw 148in disk I/O wait 149.It pw 150waiting for paging 151.It sl 152sleeping 153.El 154.Pp 155The virtual memory section shows: 156.Pp 157.Bl -tag -width abcdefgh -compact 158.It total-v 159Total virtual memory 160.It active-v 161Active virtual memory in use 162.It active-r 163Active real memory in use 164.It vm-sh 165Shared virtual memory 166.It avm-sh 167Active shared virtual memory 168.It rm-sh 169Shared real memory 170.It arm-sh 171Active shared real memory 172.It free 173Free memory 174.El 175.Pp 176All memory values are shown in number of pages. 177.It Fl U 178Dump all UVM histories. 179.It Fl u Ar histname 180Dump the specified UVM history. 181.It Fl v 182Print more verbose information. 183When used with the 184.Fl i , 185.Fl e , 186or 187.Fl m 188options prints out all counters, not just those with non-zero values. 189.It Fl W 190Print more verbose information about kernel memory pools. 191.It Fl w Ar wait 192Pause 193.Ar wait 194seconds between each display. 195If no repeat 196.Ar count 197is specified, the default is infinity. 198The 199.Nm 200command will accept and honor a negative number of 201.Ar wait 202seconds. 203.El 204.Pp 205By default, 206.Nm 207displays the following information: 208.Bl -tag -width memory 209.It procs 210Information about the numbers of processes in various states. 211.Pp 212.Bl -tag -width abcd -compact 213.It r 214in run queue 215.It b 216blocked for resources (i/o, paging, etc.) 217.El 218.It memory 219Information about the usage of virtual and real memory. 220Virtual pages (reported in units of 1024 bytes) are considered active if 221they belong to processes which are running or have run in the last 20 222seconds. 223.Pp 224.Bl -tag -width abcd -compact 225.It avm 226active virtual pages 227.It fre 228size of the free list 229.El 230.It page 231Information about page faults and paging activity. 232These are averaged every five seconds, and given in units per second. 233.Pp 234.Bl -tag -width abcd -compact 235.It flt 236total page faults 237.It re 238page reclaims (simulating reference bits) 239.It pi 240pages paged in 241.It po 242pages paged out 243.It fr 244pages freed per second 245.It sr 246pages scanned by clock algorithm, per-second 247.El 248.It disks 249Disk transfers per second. 250Typically paging will be split across the available drives. 251The header of the field is the first character of the disk name and 252the unit number. 253If more than four disk drives are configured in the system, 254.Nm 255displays only the first four drives. 256To force 257.Nm 258to display specific drives, their names may be supplied on the command line. 259.It faults 260Trap/interrupt rate averages per second over last 5 seconds. 261.Pp 262.Bl -tag -width abcd -compact 263.It in 264device interrupts per interval (including clock interrupts) 265.It sy 266system calls per interval 267.It cs 268CPU context switch rate (switches/interval) 269.El 270.It cpu 271Breakdown of percentage usage of CPU time. 272.Pp 273.Bl -tag -width abcd -compact 274.It us 275user time for normal and low priority processes 276.It sy 277system time 278.It id 279CPU idle 280.El 281.El 282.Sh FILES 283.Bl -tag -width eeenymeeny -compact 284.It Pa /netbsd 285default kernel namelist 286.It Pa /dev/mem 287default memory file 288.El 289.Sh EXAMPLES 290The command 291.Dq Li vmstat -w 5 292will print what the system is doing every five 293seconds; this is a good choice of printing interval since this is how often 294some of the statistics are sampled in the system. 295Others vary every second and running the output for a while will make it 296apparent which are recomputed every second. 297.Sh SEE ALSO 298.Xr fstat 1 , 299.Xr netstat 1 , 300.Xr nfsstat 1 , 301.Xr ps 1 , 302.Xr systat 1 , 303.Xr iostat 8 , 304.Xr pstat 8 , 305.Xr kernhist 9 306.Sh BUGS 307The 308.Fl c , 309.Fl n , 310and 311.Fl w 312options are only available with the default output. 313.Pp 314The 315.Fl l , 316.Fl U , 317and 318.Fl u 319options are useful only if the system was compiled with support for UVM 320history. 321