ARCSTAT(1)
👑 arcstat — the manual page, but make it a group chat
okay so bestie, welcome to arcstat(1) from the General Commands Manual 💖 this is the one that spills all the tea about your ZFS ARC and L2ARC, no cap.
✨ NAME ✨
arcstat — report ZFS ARC and L2ARC statistics 🦋
🌸 SYNOPSIS 🌸
arcstat [-havxp] [-f field[,field…]] [-o file] [-s string] [interval]
[count]💅 DESCRIPTION 💅
arcstat prints a whole buffet of ZFS ARC and L2ARC statistics, and it does it in a vmstat-like fashion — like, same energy, different stats. Here's the full roster, every single one, no skips 🫶:
c— ARC target sizedh%— Demand hit percentagedi%— Demand I/O hit percentagedm%— Demand miss percentageddh%— Demand data hit percentageddi%— Demand data I/O hit percentageddm%— Demand data miss percentagedmh%— Demand metadata hit percentagedmi%— Demand metadata I/O hit percentagedmm%— Demand metadata miss percentagemfu— MFU list hits per secondmh%— Metadata hit percentagemi%— Metadata I/O hit percentagemm%— Metadata miss percentagemru— MRU list hits per secondph%— Prefetch hits percentagepi%— Prefetch I/O hits percentagepm%— Prefetch miss percentagepdh%— Prefetch data hits percentagepdi%— Prefetch data I/O hits percentagepdm%— Prefetch data miss percentagepmh%— Prefetch metadata hits percentagepmi%— Prefetch metadata I/O hits percentagepmm%— Prefetch metadata miss percentagedhit— Demand hits per seconddioh— Demand I/O hits per seconddmis— Demand misses per secondddhit— Demand data hits per secondddioh— Demand data I/O hits per secondddmis— Demand data misses per seconddmhit— Demand metadata hits per seconddmioh— Demand metadata I/O hits per seconddmmis— Demand metadata misses per secondhit%— ARC hit percentagehits— ARC hits per secondioh%— ARC I/O hits percentageiohs— ARC I/O hits per secondmfug— MFU ghost list hits per secondmhit— Metadata hits per secondmioh— Metadata I/O hits per secondmiss— ARC misses per secondmmis— Metadata misses per secondmrug— MRU ghost list hits per secondphit— Prefetch hits per secondpioh— Prefetch I/O hits per secondpmis— Prefetch misses per secondpdhit— Prefetch data hits per secondpdioh— Prefetch data I/O hits per secondpdmis— Prefetch data misses per secondpmhit— Prefetch metadata hits per secondpmioh— Prefetch metadata I/O hits per secondpmmis— Prefetch metadata misses per secondread— Total ARC accesses per secondtime— Current timesize— ARC sizearcsz— Alias forsizeunc— Uncached list hits per seconddread— Demand accesses per secondddread— Demand data accesses per seconddmread— Demand metadata accesses per secondeskip—evict_skipper secondmiss%— ARC miss percentagemread— Metadata accesses per secondpread— Prefetch accesses per secondpdread— Prefetch data accesses per secondpmread— Prefetch metadata accesses per secondl2hit%— L2ARC access hit percentagel2hits— L2ARC hits per secondl2miss— L2ARC misses per secondl2read— Total L2ARC accesses per secondl2pref— L2ARC prefetch allocated size per secondl2pref%— L2ARC prefetch allocated size percentagel2mfu— L2ARC MFU allocated size per secondl2mfu%— L2ARC MFU allocated size percentagel2mru— L2ARC MRU allocated size per secondl2mru%— L2ARC MRU allocated size percentagel2data— L2ARC data (buf content) allocated size per secondl2data%— L2ARC data (buf content) allocated size percentagel2meta— L2ARC metadata (buf content) allocated size per secondl2meta%— L2ARC metadata (buf content) allocated size percentagel2size— Size of the L2ARCmtxmis—mutex_missper secondl2bytes— Bytes read per second from the L2ARCl2miss%— L2ARC access miss percentagel2asize— Actual (compressed) size of the L2ARCgrow— ARC grow disabledneed— ARC reclaim neededfree— The ARC's idea of how much free memory there is, which includes evictable memory in the page cache. Since the ARC tries to keepavailabove zero,availis usually more instructive to observe thanfree. 👀avail— The ARC's idea of how much free memory is available to it, which is a bit less thanfree. May temporarily be negative, in which case the ARC will reduce the target sizec. 😭
🎀 OPTIONS 🎀
-a— Print all possible stats. literally all of them 💅-f— Display only specific fields. See “DESCRIPTION” for supported statistics. pick your faves ✨-h— Display help message.-o— Report statistics to a file instead of the standard output.-p— Disable auto-scaling of numerical fields (for raw, machine-parsable values).-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:
interval— Specify the sampling interval in seconds.count— Display onlycountreports.
ok that's the whole page, every flag and every stat accounted for, we did not skip a single one 💖
OpenZFS • December 23, 2022 — that's the source, the version and the date bestie, and that's a wrap 🎀💜✨
📦 where this page comes from
- debian trixie: zfsutils-linux 2.3.9-0+deb13u1 · CDDL-1.0
- ubuntu noble: zfsutils-linux 2.2.2-0ubuntu9 · CDDL-1.0
- ubuntu noble: zfsutils-linux 2.2.2-0ubuntu9.5 · CDDL-1.0
- ubuntu questing: zfsutils-linux 2.3.4-1ubuntu2
- Copyright 2014 Adam Stevko. All rights reserved
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