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Copyright 2014 Adam Stevko. All rights reserved.
Copyright (c) 2015 by Delphix. All rights reserved.

ARCSTAT 8 "Feb 4, 2014"
NAME
arcstat - report ZFS ARC and L2ARC statistics
SYNOPSIS
arcstat [-hvxr] [-f field[,field]...] [-o file] [-s string]
 [interval [count]]
DESCRIPTION
The arcstat utility print various ZFS ARC and L2ARC statistics in vmstat-like fashion.

The arcstat command reports the following information:
c

ARC Target Size

dh%

Demand Data hit percentage

dm%

Demand Data miss percentage

mfu

MFU List hits per second

mh%

Metadata hit percentage

mm%

Metadata miss percentage

mru

MRU List hits per second

ph%

Prefetch hits percentage

pm%

Prefetch miss percentage

dhit

Demand Data hits per second

dmis

Demand Data misses per second

hit%

ARC Hit percentage

hits

ARC reads per second

mfug

MFU Ghost List hits per second

mhit

Metadata hits per second

miss

ARC misses per second

mmis

Metadata misses per second

mrug

MRU Ghost List hits per second

phit

Prefetch hits per second

pmis

Prefetch misses per second

read

Total ARC accesses per second

time

Time

arcsz

ARC Size

dread

Demand data accesses per second

eskip

evict_skip per second

miss%

ARC miss percentage

mread

Metadata accesses per second

pread

Prefetch accesses per second

l2hit%

L2ARC access hit percentage

l2hits

L2ARC hits per second

l2miss

L2ARC misses per second

l2read

Total L2ARC accesses per second

l2pref

L2ARC prefetch allocated size per second

l2pref%

L2ARC prefetch allocated size percentage

l2mfu

L2ARC MFU allocated size per second

l2mfu%

L2ARC MFU allocated size percentage

l2mru

L2ARC MRU allocated size per second

l2mru%

L2ARC MRU allocated size percentage

l2data

L2ARC data (buf content) allocated size per second

l2data%

L2ARC data (buf content) allocated size percentage

l2meta

L2ARC metadata (buf content) allocated size per second

l2meta%

L2ARC metadata (buf content) allocated size percentage

l2size

Size of the L2ARC

mtxmis

mutex_miss per second

l2bytes

bytes read per second from the L2ARC

l2miss%

L2ARC access miss percentage

l2asize

Actual (compressed) size of the L2ARC


OPTIONS
The following options are supported: -f

Display only specific fields. See DESCRIPTION for supported statistics.

-h

Display help message.

-o

Report statistics to a file instead of the standard output.

-s

Display data with a specified separator (default: 2 spaces).

-x

Print extended stats (same as -f time,mfu,mru,mfug,mrug,eskip,mtxmis,dread,pread,read).

-v

Show field headers and definitions

OPERANDS
The following operands are supported: count

Display only count reports.

interval

Specify the sampling interval in seconds.

AUTHORS
arcstat was originally written by Neelakanth Nadgir and supported only ZFS ARC statistics. Mike Harsch updated it to support L2ARC statistics.