diff options
Diffstat (limited to 'man/vmstat.8')
| -rw-r--r-- | man/vmstat.8 | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/man/vmstat.8 b/man/vmstat.8 new file mode 100644 index 0000000..bfaba27 --- /dev/null +++ b/man/vmstat.8 @@ -0,0 +1,202 @@ +.\" +.\" Copyright (c) 2002-2023 Craig Small <csmall@dropbear.xyz> +.\" Copyright (c) 2012-2023 Jim Warner <james.warner@comcast.net> +.\" Copyright (c) 2011-2012 Sami Kerola <kerolasa@iki.fi> +.\" Copyright (c) 1994 Henry Ware <al172@yfn.ysu.edu> +.\" +.\" This program is free software; you can redistribute it and/or modify +.\" it under the terms of the GNU General Public License as published by +.\" the Free Software Foundation; either version 2 of the License, or +.\" (at your option) any later version. +.\" +.\" +.TH VMSTAT 8 "2023-01-18" "procps-ng" "System Administration" +.SH NAME +vmstat \- Report virtual memory statistics +.SH SYNOPSIS +.B vmstat +[options] +.RI [ delay " [" count ]] +.SH DESCRIPTION +.B vmstat +reports information about processes, memory, paging, block IO, traps, disks +and cpu activity. +.PP +The first report produced gives averages since the last reboot. Additional +reports give information on a sampling period of length +.IR delay . +The process and memory reports are instantaneous in either case. +.SH OPTIONS +.TP +.I delay +The +.I delay +between updates in seconds. If no +.I delay +is specified, only one report is printed with the average values since boot. +.TP +.I count +Number of updates. In absence of +.IR count , +when +.I delay +is defined, default is infinite. +.TP +\fB\-a\fR, \fB\-\-active\fR +Display active and inactive memory, given a 2.5.41 kernel or better. +.TP +\fB\-f\fR, \fB\-\-forks\fR +The +.B \-f +switch displays the number of forks since boot. This includes the fork, +vfork, and clone system calls, and is equivalent to the total number of tasks +created. Each process is represented by one or more tasks, depending on +thread usage. This display does not repeat. +.TP +\fB\-m\fR, \fB\-\-slabs\fR +Displays slabinfo. +.TP +\fB\-n\fR, \fB\-\-one-header\fR +Display the header only once rather than periodically. +.TP +\fB\-s\fR, \fB\-\-stats\fR +Displays a table of various event counters and memory statistics. This +display does not repeat. +.TP +\fB\-d\fR, \fB\-\-disk\fR +Report disk statistics (2.5.70 or above required). +.TP +\fB\-D\fR, \fB\-\-disk-sum\fR +Report some summary statistics about disk activity. +.TP +\fB\-p\fR, \fB\-\-partition\fR \fIdevice\fR +Detailed statistics about partition (2.5.70 or above required). +.TP +\fB\-S\fR, \fB\-\-unit\fR \fIcharacter\fR +Switches outputs between 1000 +.RI ( k ), +1024 +.RI ( K ), +1000000 +.RI ( m ), +or 1048576 +.RI ( M ) +bytes. Note this does not change the swap (si/so) or block (bi/bo) +fields. +.TP +\fB\-t\fR, \fB\-\-timestamp\fR +Append timestamp to each line +.TP +\fB\-w\fR, \fB\-\-wide\fR +Wide output mode (useful for systems with higher amount of memory, +where the default output mode suffers from unwanted column breakage). +The output is wider than 80 characters per line. +.TP +\fB\-y\fR, \fB\-\-no-first\fR +Omits first report with statistics since system boot. +.TP +\fB\-V\fR, \fB\-\-version\fR +Display version information and exit. +.TP +\fB\-h\fR, \fB\-\-help\fR +Display help and exit. +.PD +.SH FIELD DESCRIPTION FOR VM MODE +.SS Procs +.nf +r: The number of runnable processes (running or waiting for run time). +b: The number of processes blocked waiting for I/O to complete. +.fi +.SS Memory +These are affected by the \fB\-\-unit\fR option. +.nf +swpd: the amount of swap memory used. +free: the amount of idle memory. +buff: the amount of memory used as buffers. +cache: the amount of memory used as cache. +inact: the amount of inactive memory. (\fB\-a\fR option) +active: the amount of active memory. (\fB\-a\fR option) +.fi +.SS Swap +These are affected by the \fB\-\-unit\fR option. +.nf +si: Amount of memory swapped in from disk (/s). +so: Amount of memory swapped to disk (/s). +.fi +.SS IO +.nf +bi: Kibibyte received from a block device (KiB/s). +bo: Kibibyte sent to a block device (KiB/s). +.fi +.SS System +.nf +in: The number of interrupts per second, including the clock. +cs: The number of context switches per second. +.fi +.SS CPU +These are percentages of total CPU time. +.nf +us: Time spent running non\-kernel code. (user time, including nice time) +sy: Time spent running kernel code. (system time) +id: Time spent idle. Prior to Linux 2.5.41, this includes IO\-wait time. +wa: Time spent waiting for IO. Prior to Linux 2.5.41, included in idle. +st: Time stolen from a virtual machine. Prior to Linux 2.6.11, unknown. +gu: Time spent running KVM guest code (guest time, including guest nice). +.fi +.SH FIELD DESCRIPTION FOR DISK MODE +.SS Reads +.nf +total: Total reads completed successfully +merged: grouped reads (resulting in one I/O) +sectors: Sectors read successfully +ms: milliseconds spent reading +.fi +.SS Writes +.nf +total: Total writes completed successfully +merged: grouped writes (resulting in one I/O) +sectors: Sectors written successfully +ms: milliseconds spent writing +.fi +.SS IO +.nf +cur: I/O in progress +s: seconds spent for I/O +.fi +.SH FIELD DESCRIPTION FOR DISK PARTITION MODE +.nf +reads: Total number of reads issued to this partition +read sectors: Total read sectors for partition +writes : Total number of writes issued to this partition +requested writes: Total number of write requests made for partition +.fi +.SH FIELD DESCRIPTION FOR SLAB MODE +Slab mode shows statistics per slab, for more information +about this information see +.BR slabinfo (5) +.PP +.nf +cache: Cache name +num: Number of currently active objects +total: Total number of available objects +size: Size of each object +pages: Number of pages with at least one active object +.fi +.SH NOTES +.B vmstat +requires read access to files under \fI/proc\fR. The \fB\-m\fR requires read +access to \fI/proc/slabinfo\fR which may not be available to standard users. +Mount options for \fI/proc\fR such as \fIsubset=pid\fR may also impact what +is visible. +.SH "SEE ALSO" +.BR free (1), +.BR iostat (1), +.BR mpstat (1), +.BR ps (1), +.BR sar (1), +.BR top (1), +.BR slabinfo (5) +.SH "REPORTING BUGS" +Please send bug reports to +.UR procps@freelists.org +.UE |