arcstat.1: modernise

Also slim down the description a tad

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12125
This commit is contained in:
наб 2021-05-26 14:27:13 +02:00 committed by Brian Behlendorf
parent 8134178f3b
commit 639871363a

View File

@ -8,603 +8,175 @@
.\" source. A copy of the CDDL is also available via the Internet at .\" source. A copy of the CDDL is also available via the Internet at
.\" http://www.illumos.org/license/CDDL. .\" http://www.illumos.org/license/CDDL.
.\" .\"
.\"
.\" Copyright 2014 Adam Stevko. All rights reserved. .\" Copyright 2014 Adam Stevko. All rights reserved.
.\" Copyright (c) 2015 by Delphix. All rights reserved. .\" Copyright (c) 2015 by Delphix. All rights reserved.
.\" Copyright (c) 2020 by AJ Jordan. All rights reserved. .\" Copyright (c) 2020 by AJ Jordan. All rights reserved.
.\" .\"
.TH ARCSTAT 1 "Oct 20, 2020" OpenZFS .Dd May 26, 2021
.SH NAME .Dt ARCSTAT 1
arcstat \- report ZFS ARC and L2ARC statistics .Os
.SH SYNOPSIS .
.LP .Sh NAME
.nf .Nm arcstat
\fBarcstat\fR [\fB-havxp\fR] [\fB-f field[,field]...\fR] [\fB-o file\fR] [\fB-s string\fR] [\fBinterval\fR [\fBcount\fR]] .Nd report ZFS ARC and L2ARC statistics
.fi .Sh SYNOPSIS
.Nm
.SH DESCRIPTION .Op Fl havxp
.LP .Op Fl f Ar field Ns Op , Ns Ar field Ns ...
The \fBarcstat\fR utility print various ZFS ARC and L2ARC statistics in .Op Fl o Ar file
vmstat-like fashion. .Op Fl s Ar string
.sp .Op Ar interval
.Op Ar count
.sp .
.LP .Sh DESCRIPTION
The \fBarcstat\fR command reports the following information: .Nm
.sp prints various ZFS ARC and L2ARC statistics in vmstat-like fashion:
.ne 2 .Bl -tag -width "l2asize"
.It Sy c
.\"
.sp
.ne 1
.na
\fBc \fR
.ad
.RS 14n
ARC target size ARC target size
.RE .It Sy dh%
.sp
.ne 2
.na
\fBdh% \fR
.ad
.RS 14n
Demand data hit percentage Demand data hit percentage
.RE .It Sy dm%
.sp
.ne 2
.na
\fBdm% \fR
.ad
.RS 14n
Demand data miss percentage Demand data miss percentage
.RE .It Sy mfu
.sp
.ne 2
.na
\fBmfu \fR
.ad
.RS 14n
MFU list hits per second MFU list hits per second
.RE .It Sy mh%
.sp
.ne 2
.na
\fBmh% \fR
.ad
.RS 14n
Metadata hit percentage Metadata hit percentage
.RE .It Sy mm%
.sp
.ne 2
.na
\fBmm% \fR
.ad
.RS 14n
Metadata miss percentage Metadata miss percentage
.RE .It Sy mru
.sp
.ne 2
.na
\fBmru \fR
.ad
.RS 14n
MRU list hits per second MRU list hits per second
.RE .It Sy ph%
.sp
.ne 2
.na
\fBph% \fR
.ad
.RS 14n
Prefetch hits percentage Prefetch hits percentage
.RE .It Sy pm%
.sp
.ne 2
.na
\fBpm% \fR
.ad
.RS 14n
Prefetch miss percentage Prefetch miss percentage
.RE .It Sy dhit
.sp
.ne 2
.na
\fBdhit \fR
.ad
.RS 14n
Demand data hits per second Demand data hits per second
.RE .It Sy dmis
.sp
.ne 2
.na
\fBdmis \fR
.ad
.RS 14n
Demand data misses per second Demand data misses per second
.RE .It Sy hit%
.sp
.ne 2
.na
\fBhit% \fR
.ad
.RS 14n
ARC hit percentage ARC hit percentage
.RE .It Sy hits
.sp
.ne 2
.na
\fBhits \fR
.ad
.RS 14n
ARC reads per second ARC reads per second
.RE .It Sy mfug
.sp
.ne 2
.na
\fBmfug \fR
.ad
.RS 14n
MFU ghost list hits per second MFU ghost list hits per second
.RE .It Sy mhit
.sp
.ne 2
.na
\fBmhit \fR
.ad
.RS 14n
Metadata hits per second Metadata hits per second
.RE .It Sy miss
.sp
.ne 2
.na
\fBmiss \fR
.ad
.RS 14n
ARC misses per second ARC misses per second
.RE .It Sy mmis
.sp
.ne 2
.na
\fBmmis \fR
.ad
.RS 14n
Metadata misses per second Metadata misses per second
.RE .It Sy mrug
.sp
.ne 2
.na
\fBmrug \fR
.ad
.RS 14n
MRU ghost list hits per second MRU ghost list hits per second
.RE .It Sy phit
.sp
.ne 2
.na
\fBphit \fR
.ad
.RS 14n
Prefetch hits per second Prefetch hits per second
.RE .It Sy pmis
.sp
.ne 2
.na
\fBpmis \fR
.ad
.RS 14n
Prefetch misses per second Prefetch misses per second
.RE .It Sy read
.sp
.ne 2
.na
\fBread \fR
.ad
.RS 14n
Total ARC accesses per second Total ARC accesses per second
.RE .It Sy time
Current time
.sp .It Sy size
.ne 2
.na
\fBtime \fR
.ad
.RS 14n
Time
.RE
.sp
.ne 2
.na
\fBsize \fR
.ad
.RS 14n
ARC size ARC size
.RE .It Sy arcsz
Alias for
.sp .Sy size
.ne 2 .It Sy dread
.na
\fBarcsz \fR
.ad
.RS 14n
Alias for \fBsize\fR
.RE
.sp
.ne 2
.na
\fBdread \fR
.ad
.RS 14n
Demand data accesses per second Demand data accesses per second
.RE .It Sy eskip
.sp
.ne 2
.na
\fBeskip \fR
.ad
.RS 14n
evict_skip per second evict_skip per second
.RE .It Sy miss%
.sp
.ne 2
.na
\fBmiss% \fR
.ad
.RS 14n
ARC miss percentage ARC miss percentage
.RE .It Sy mread
.sp
.ne 2
.na
\fBmread \fR
.ad
.RS 14n
Metadata accesses per second Metadata accesses per second
.RE .It Sy pread
.sp
.ne 2
.na
\fBpread \fR
.ad
.RS 14n
Prefetch accesses per second Prefetch accesses per second
.RE .It Sy l2hit%
.sp
.ne 2
.na
\fBl2hit% \fR
.ad
.RS 14n
L2ARC access hit percentage L2ARC access hit percentage
.RE .It Sy l2hits
.sp
.ne 2
.na
\fBl2hits \fR
.ad
.RS 14n
L2ARC hits per second L2ARC hits per second
.RE .It Sy l2miss
.sp
.ne 2
.na
\fBl2miss \fR
.ad
.RS 14n
L2ARC misses per second L2ARC misses per second
.RE .It Sy l2read
.sp
.ne 2
.na
\fBl2read \fR
.ad
.RS 14n
Total L2ARC accesses per second Total L2ARC accesses per second
.RE .It Sy l2pref
.sp
.ne 2
.na
\fBl2pref \fR
.ad
.RS 14n
L2ARC prefetch allocated size per second L2ARC prefetch allocated size per second
.RE .It Sy l2pref%
.sp
.ne 2
.na
\fBl2pref% \fR
.ad
.RS 14n
L2ARC prefetch allocated size percentage L2ARC prefetch allocated size percentage
.RE .It Sy l2mfu
.sp
.ne 2
.na
\fBl2mfu \fR
.ad
.RS 14n
L2ARC MFU allocated size per second L2ARC MFU allocated size per second
.RE .It Sy l2mfu%
.sp
.ne 2
.na
\fBl2mfu% \fR
.ad
.RS 14n
L2ARC MFU allocated size percentage L2ARC MFU allocated size percentage
.RE .It Sy l2mru
.sp
.ne 2
.na
\fBl2mru \fR
.ad
.RS 14n
L2ARC MRU allocated size per second L2ARC MRU allocated size per second
.RE .It Sy l2mru%
.sp
.ne 2
.na
\fBl2mru% \fR
.ad
.RS 14n
L2ARC MRU allocated size percentage L2ARC MRU allocated size percentage
.RE .It Sy l2data
.sp
.ne 2
.na
\fBl2data \fR
.ad
.RS 14n
L2ARC data (buf content) allocated size per second L2ARC data (buf content) allocated size per second
.RE .It Sy l2data%
.sp
.ne 2
.na
\fBl2data% \fR
.ad
.RS 14n
L2ARC data (buf content) allocated size percentage L2ARC data (buf content) allocated size percentage
.RE .It Sy l2meta
.sp
.ne 2
.na
\fBl2meta \fR
.ad
.RS 14n
L2ARC metadata (buf content) allocated size per second L2ARC metadata (buf content) allocated size per second
.RE .It Sy l2meta%
.sp
.ne 2
.na
\fBl2meta% \fR
.ad
.RS 14n
L2ARC metadata (buf content) allocated size percentage L2ARC metadata (buf content) allocated size percentage
.RE .It Sy l2size
.sp
.ne 2
.na
\fBl2size \fR
.ad
.RS 14n
Size of the L2ARC Size of the L2ARC
.RE .It Sy mtxmis
.sp
.ne 2
.na
\fBmtxmis \fR
.ad
.RS 14n
mutex_miss per second mutex_miss per second
.RE .It Sy l2bytes
.sp
.ne 2
.na
\fBl2bytes \fR
.ad
.RS 14n
Bytes read per second from the L2ARC Bytes read per second from the L2ARC
.RE .It Sy l2miss%
.sp
.ne 2
.na
\fBl2miss% \fR
.ad
.RS 14n
L2ARC access miss percentage L2ARC access miss percentage
.RE .It Sy l2asize
.sp
.ne 2
.na
\fBl2asize \fR
.ad
.RS 14n
Actual (compressed) size of the L2ARC Actual (compressed) size of the L2ARC
.RE .It Sy grow
.sp
.ne 2
.na
\fBgrow \fR
.ad
.RS 14n
ARC grow disabled ARC grow disabled
.RE .It Sy need
.sp
.ne 2
.na
\fBneed \fR
.ad
.RS 14n
ARC reclaim needed ARC reclaim needed
.RE .It Sy free
.sp
.ne 2
.na
\fBfree \fR
.ad
.RS 14n
The ARC's idea of how much free memory there is, which includes evictable memory in the page cache. The ARC's idea of how much free memory there is, which includes evictable memory in the page cache.
Since the ARC tries to keep \fBavail\fR above zero, \fBavail\fR is usually more instructive to observe than \fBfree\fR. Since the ARC tries to keep
.RE .Sy avail
above zero,
.sp .Sy avail
.ne 2 is usually more instructive to observe than
.na .Sy free .
\fBavail \fR .It Sy avail
.ad The ARC's idea of how much free memory is available to it, which is a bit less than
.RS 14n .Sy free .
The ARC's idea of how much free memory is available to it, which is a bit less than \fBfree\fR. May temporarily be negative, in which case the ARC will reduce the target size
May temporarily be negative, in which case the ARC will reduce the target size \fBc\fR. .Sy c .
.RE .El
.\" .
.Sh OPTIONS
.SH OPTIONS .Bl -tag -width "-v"
.LP .It Fl a
The following options are supported:
.sp
.ne 2
.na
\fB\fB-a\fR\fR
.ad
.RS 12n
Print all possible stats. Print all possible stats.
.RE .It Fl f
Display only specific fields.
.sp See
.ne 2 .Sy DESCRIPTION
.na for supported statistics.
\fB\fB-f\fR\fR .It Fl h
.ad
.RS 12n
Display only specific fields. See \fBDESCRIPTION\fR for supported statistics.
.RE
.sp
.ne 2
.na
\fB\fB-h\fR\fR
.ad
.RS 12n
Display help message. Display help message.
.RE .It Fl o
.sp
.ne 2
.na
\fB\fB-o\fR\fR
.ad
.RS 12n
Report statistics to a file instead of the standard output. Report statistics to a file instead of the standard output.
.RE .It Fl p
.sp
.ne 2
.na
\fB\fB-p\fR\fR
.ad
.RS 12n
Disable auto-scaling of numerical fields (for raw, machine-parsable values). Disable auto-scaling of numerical fields (for raw, machine-parsable values).
.RE .It Fl s
.sp
.ne 2
.na
\fB\fB-s\fR\fR
.ad
.RS 12n
Display data with a specified separator (default: 2 spaces). Display data with a specified separator (default: 2 spaces).
.RE .It Fl x
Print extended stats (same as
.sp .Fl f Ar time,mfu,mru,mfug,mrug,eskip,mtxmis,dread,pread,read Ns No ).
.ne 2 .It Fl v
.na
\fB\fB-x\fR\fR
.ad
.RS 12n
Print extended stats (same as -f time,mfu,mru,mfug,mrug,eskip,mtxmis,dread,pread,read).
.RE
.sp
.ne 2
.na
\fB\fB-v\fR\fR
.ad
.RS 12n
Show field headers and definitions Show field headers and definitions
.RE .El
.
.SH OPERANDS .Sh OPERANDS
.LP
The following operands are supported: The following operands are supported:
.sp .Bl -tag -width "interval"
.ne 2 .It Ar interval
.na
\fB\fIcount\fR\fR
.ad
.RS 12n
Display only \fIcount\fR reports.
.RE
.sp
.ne 2
.na
\fB\fIinterval\fR\fR
.ad
.RS 12n
Specify the sampling interval in seconds. Specify the sampling interval in seconds.
.RE .It Ar count
Display only \fIcount\fR reports.
.SH AUTHORS .El
.LP
arcstat was originally written in Perl by Neelakanth Nadgir and supported only ZFS ARC statistics.
Mike Harsch updated it to support L2ARC statistics.
John Hixson ported it to Python for FreeNAS over some beer, after which many individuals from the OpenZFS community continued to maintain and improve it.