1eda14cbcSMatt Macy.\" 2eda14cbcSMatt Macy.\" This file and its contents are supplied under the terms of the 3eda14cbcSMatt Macy.\" Common Development and Distribution License ("CDDL"), version 1.0. 4eda14cbcSMatt Macy.\" You may only use this file in accordance with the terms of version 5eda14cbcSMatt Macy.\" 1.0 of the CDDL. 6eda14cbcSMatt Macy.\" 7eda14cbcSMatt Macy.\" A full copy of the text of the CDDL should have accompanied this 8eda14cbcSMatt Macy.\" source. A copy of the CDDL is also available via the Internet at 9eda14cbcSMatt Macy.\" http://www.illumos.org/license/CDDL. 10eda14cbcSMatt Macy.\" 11eda14cbcSMatt Macy.\" Copyright 2012, Richard Lowe. 12eda14cbcSMatt Macy.\" Copyright (c) 2012, 2019 by Delphix. All rights reserved. 13eda14cbcSMatt Macy.\" Copyright 2017 Nexenta Systems, Inc. 14eda14cbcSMatt Macy.\" Copyright (c) 2017 Lawrence Livermore National Security, LLC. 15eda14cbcSMatt Macy.\" Copyright (c) 2017 Intel Corporation. 16eda14cbcSMatt Macy.\" 17184c1b94SMartin Matuska.Dd October 7, 2020 1816038816SMartin Matuska.Dt ZDB 8 19eda14cbcSMatt Macy.Os 2016038816SMartin Matuska. 21eda14cbcSMatt Macy.Sh NAME 22eda14cbcSMatt Macy.Nm zdb 2316038816SMartin Matuska.Nd display ZFS storage pool debugging and consistency information 24eda14cbcSMatt Macy.Sh SYNOPSIS 25eda14cbcSMatt Macy.Nm 26eda14cbcSMatt Macy.Op Fl AbcdDFGhikLMPsvXYy 2716038816SMartin Matuska.Op Fl e Oo Fl V Oc Oo Fl p Ar path Oc Ns … 28eda14cbcSMatt Macy.Op Fl I Ar inflight I/Os 2916038816SMartin Matuska.Oo Fl o Ar var Ns = Ns Ar value Oc Ns … 30eda14cbcSMatt Macy.Op Fl t Ar txg 31eda14cbcSMatt Macy.Op Fl U Ar cache 32eda14cbcSMatt Macy.Op Fl x Ar dumpdir 3316038816SMartin Matuska.Op Ar poolname Ns Op / Ns Ar dataset | objset ID 3416038816SMartin Matuska.Op Ar object Ns | Ns Ar range Ns … 35eda14cbcSMatt Macy.Nm 36eda14cbcSMatt Macy.Op Fl AdiPv 3716038816SMartin Matuska.Op Fl e Oo Fl V Oc Oo Fl p Ar path Oc Ns … 38eda14cbcSMatt Macy.Op Fl U Ar cache 3916038816SMartin Matuska.Ar poolname Ns Op Ar / Ns Ar dataset | objset ID 4016038816SMartin Matuska.Op Ar object Ns | Ns Ar range Ns … 41eda14cbcSMatt Macy.Nm 42eda14cbcSMatt Macy.Fl C 43eda14cbcSMatt Macy.Op Fl A 44eda14cbcSMatt Macy.Op Fl U Ar cache 45eda14cbcSMatt Macy.Nm 46eda14cbcSMatt Macy.Fl E 47eda14cbcSMatt Macy.Op Fl A 4816038816SMartin Matuska.Ar word0 : Ns Ar word1 Ns :…: Ns Ar word15 49eda14cbcSMatt Macy.Nm 50eda14cbcSMatt Macy.Fl l 51eda14cbcSMatt Macy.Op Fl Aqu 52eda14cbcSMatt Macy.Ar device 53eda14cbcSMatt Macy.Nm 54eda14cbcSMatt Macy.Fl m 55eda14cbcSMatt Macy.Op Fl AFLPXY 5616038816SMartin Matuska.Op Fl e Oo Fl V Oc Oo Fl p Ar path Oc Ns … 57eda14cbcSMatt Macy.Op Fl t Ar txg 58eda14cbcSMatt Macy.Op Fl U Ar cache 5916038816SMartin Matuska.Ar poolname Op Ar vdev Oo Ar metaslab Oc Ns … 60eda14cbcSMatt Macy.Nm 61eda14cbcSMatt Macy.Fl O 62eda14cbcSMatt Macy.Ar dataset path 63eda14cbcSMatt Macy.Nm 64184c1b94SMartin Matuska.Fl r 65184c1b94SMartin Matuska.Ar dataset path destination 66184c1b94SMartin Matuska.Nm 67eda14cbcSMatt Macy.Fl R 68eda14cbcSMatt Macy.Op Fl A 6916038816SMartin Matuska.Op Fl e Oo Fl V Oc Oo Fl p Ar path Oc Ns … 70eda14cbcSMatt Macy.Op Fl U Ar cache 7116038816SMartin Matuska.Ar poolname vdev : Ns Ar offset : Ns Oo Ar lsize Ns / Oc Ns Ar psize Ns Op : Ns Ar flags 72eda14cbcSMatt Macy.Nm 73eda14cbcSMatt Macy.Fl S 74eda14cbcSMatt Macy.Op Fl AP 7516038816SMartin Matuska.Op Fl e Oo Fl V Oc Oo Fl p Ar path Oc Ns … 76eda14cbcSMatt Macy.Op Fl U Ar cache 77eda14cbcSMatt Macy.Ar poolname 7816038816SMartin Matuska. 79eda14cbcSMatt Macy.Sh DESCRIPTION 80eda14cbcSMatt MacyThe 81eda14cbcSMatt Macy.Nm 82eda14cbcSMatt Macyutility displays information about a ZFS pool useful for debugging and performs 83eda14cbcSMatt Macysome amount of consistency checking. 84eda14cbcSMatt MacyIt is a not a general purpose tool and options 85eda14cbcSMatt Macy.Pq and facilities 86eda14cbcSMatt Macymay change. 87eda14cbcSMatt MacyThis is not a 88eda14cbcSMatt Macy.Xr fsck 8 89eda14cbcSMatt Macyutility. 90eda14cbcSMatt Macy.Pp 91eda14cbcSMatt MacyThe output of this command in general reflects the on-disk structure of a ZFS 92eda14cbcSMatt Macypool, and is inherently unstable. 93eda14cbcSMatt MacyThe precise output of most invocations is not documented, a knowledge of ZFS 94eda14cbcSMatt Macyinternals is assumed. 95eda14cbcSMatt Macy.Pp 96eda14cbcSMatt MacyIf the 97eda14cbcSMatt Macy.Ar dataset 98eda14cbcSMatt Macyargument does not contain any 99eda14cbcSMatt Macy.Qq Sy / 100eda14cbcSMatt Macyor 101eda14cbcSMatt Macy.Qq Sy @ 102eda14cbcSMatt Macycharacters, it is interpreted as a pool name. 103eda14cbcSMatt MacyThe root dataset can be specified as 10416038816SMartin Matuska.Qq Ar pool Ns / . 105eda14cbcSMatt Macy.Pp 106eda14cbcSMatt MacyWhen operating on an imported and active pool it is possible, though unlikely, 107eda14cbcSMatt Macythat zdb may interpret inconsistent pool data and behave erratically. 10816038816SMartin Matuska. 109eda14cbcSMatt Macy.Sh OPTIONS 110eda14cbcSMatt MacyDisplay options: 111eda14cbcSMatt Macy.Bl -tag -width Ds 112eda14cbcSMatt Macy.It Fl b 113eda14cbcSMatt MacyDisplay statistics regarding the number, size 114eda14cbcSMatt Macy.Pq logical, physical and allocated 115eda14cbcSMatt Macyand deduplication of blocks. 116eda14cbcSMatt Macy.It Fl c 117eda14cbcSMatt MacyVerify the checksum of all metadata blocks while printing block statistics 118eda14cbcSMatt Macy.Po see 119eda14cbcSMatt Macy.Fl b 120eda14cbcSMatt Macy.Pc . 121eda14cbcSMatt Macy.Pp 122eda14cbcSMatt MacyIf specified multiple times, verify the checksums of all blocks. 123eda14cbcSMatt Macy.It Fl C 124eda14cbcSMatt MacyDisplay information about the configuration. 125eda14cbcSMatt MacyIf specified with no other options, instead display information about the cache 126eda14cbcSMatt Macyfile 127eda14cbcSMatt Macy.Pq Pa /etc/zfs/zpool.cache . 128eda14cbcSMatt MacyTo specify the cache file to display, see 129eda14cbcSMatt Macy.Fl U . 130eda14cbcSMatt Macy.Pp 131eda14cbcSMatt MacyIf specified multiple times, and a pool name is also specified display both the 132eda14cbcSMatt Macycached configuration and the on-disk configuration. 133eda14cbcSMatt MacyIf specified multiple times with 134eda14cbcSMatt Macy.Fl e 135eda14cbcSMatt Macyalso display the configuration that would be used were the pool to be imported. 136eda14cbcSMatt Macy.It Fl d 137eda14cbcSMatt MacyDisplay information about datasets. 138eda14cbcSMatt MacySpecified once, displays basic dataset information: ID, create transaction, 139eda14cbcSMatt Macysize, and object count. 140eda14cbcSMatt Macy.Pp 141eda14cbcSMatt MacyIf specified multiple times provides greater and greater verbosity. 142eda14cbcSMatt Macy.Pp 143eda14cbcSMatt MacyIf object IDs or object ID ranges are specified, display information about 144eda14cbcSMatt Macythose specific objects or ranges only. 145eda14cbcSMatt Macy.Pp 146eda14cbcSMatt MacyAn object ID range is specified in terms of a colon-separated tuple of 147eda14cbcSMatt Macythe form 14816038816SMartin Matuska.Ao start Ac : Ns Ao end Ac Ns Op : Ns Ao flags Ac . 149eda14cbcSMatt MacyThe fields 150eda14cbcSMatt Macy.Ar start 151eda14cbcSMatt Macyand 152eda14cbcSMatt Macy.Ar end 153eda14cbcSMatt Macyare integer object identifiers that denote the upper and lower bounds 15416038816SMartin Matuskaof the range. 15516038816SMartin MatuskaAn 156eda14cbcSMatt Macy.Ar end 15716038816SMartin Matuskavalue of -1 specifies a range with no upper bound. 15816038816SMartin MatuskaThe 159eda14cbcSMatt Macy.Ar flags 160eda14cbcSMatt Macyfield optionally specifies a set of flags, described below, that control 16116038816SMartin Matuskawhich object types are dumped. 16216038816SMartin MatuskaBy default, all object types are dumped. 16316038816SMartin MatuskaA minus sign 164eda14cbcSMatt Macy.Pq - 165eda14cbcSMatt Macynegates the effect of the flag that follows it and has no effect unless 166eda14cbcSMatt Macypreceded by the 167eda14cbcSMatt Macy.Ar A 16816038816SMartin Matuskaflag. 16916038816SMartin MatuskaFor example, the range 0:-1:A-d will dump all object types except for directories. 170eda14cbcSMatt Macy.Pp 17116038816SMartin Matuska.Bl -tag -compact -width Ds 172eda14cbcSMatt Macy.It Sy A 173eda14cbcSMatt MacyDump all objects (this is the default) 174eda14cbcSMatt Macy.It Sy d 175eda14cbcSMatt MacyDump ZFS directory objects 176eda14cbcSMatt Macy.It Sy f 177eda14cbcSMatt MacyDump ZFS plain file objects 178eda14cbcSMatt Macy.It Sy m 179eda14cbcSMatt MacyDump SPA space map objects 180eda14cbcSMatt Macy.It Sy z 181eda14cbcSMatt MacyDump ZAP objects 182eda14cbcSMatt Macy.It Sy - 183eda14cbcSMatt MacyNegate the effect of next flag 184eda14cbcSMatt Macy.El 185eda14cbcSMatt Macy.It Fl D 186eda14cbcSMatt MacyDisplay deduplication statistics, including the deduplication ratio 187eda14cbcSMatt Macy.Pq Sy dedup , 188eda14cbcSMatt Macycompression ratio 189eda14cbcSMatt Macy.Pq Sy compress , 190eda14cbcSMatt Macyinflation due to the zfs copies property 191eda14cbcSMatt Macy.Pq Sy copies , 192eda14cbcSMatt Macyand an overall effective ratio 193eda14cbcSMatt Macy.Pq Sy dedup No * Sy compress No / Sy copies . 194eda14cbcSMatt Macy.It Fl DD 195eda14cbcSMatt MacyDisplay a histogram of deduplication statistics, showing the allocated 196eda14cbcSMatt Macy.Pq physically present on disk 197eda14cbcSMatt Macyand referenced 198eda14cbcSMatt Macy.Pq logically referenced in the pool 199eda14cbcSMatt Macyblock counts and sizes by reference count. 200eda14cbcSMatt Macy.It Fl DDD 201eda14cbcSMatt MacyDisplay the statistics independently for each deduplication table. 202eda14cbcSMatt Macy.It Fl DDDD 203eda14cbcSMatt MacyDump the contents of the deduplication tables describing duplicate blocks. 204eda14cbcSMatt Macy.It Fl DDDDD 205eda14cbcSMatt MacyAlso dump the contents of the deduplication tables describing unique blocks. 20616038816SMartin Matuska.It Fl E Ar word0 : Ns Ar word1 Ns :…: Ns Ar word15 207eda14cbcSMatt MacyDecode and display block from an embedded block pointer specified by the 208eda14cbcSMatt Macy.Ar word 209eda14cbcSMatt Macyarguments. 210eda14cbcSMatt Macy.It Fl h 211eda14cbcSMatt MacyDisplay pool history similar to 212eda14cbcSMatt Macy.Nm zpool Cm history , 213eda14cbcSMatt Macybut include internal changes, transaction, and dataset information. 214eda14cbcSMatt Macy.It Fl i 215eda14cbcSMatt MacyDisplay information about intent log 216eda14cbcSMatt Macy.Pq ZIL 217eda14cbcSMatt Macyentries relating to each dataset. 218eda14cbcSMatt MacyIf specified multiple times, display counts of each intent log transaction type. 219eda14cbcSMatt Macy.It Fl k 220eda14cbcSMatt MacyExamine the checkpointed state of the pool. 221eda14cbcSMatt MacyNote, the on disk format of the pool is not reverted to the checkpointed state. 222eda14cbcSMatt Macy.It Fl l Ar device 223eda14cbcSMatt MacyRead the vdev labels and L2ARC header from the specified device. 224eda14cbcSMatt Macy.Nm Fl l 225eda14cbcSMatt Macywill return 0 if valid label was found, 1 if error occurred, and 2 if no valid 22616038816SMartin Matuskalabels were found. 22716038816SMartin MatuskaThe presence of L2ARC header is indicated by a specific 22816038816SMartin Matuskasequence (L2ARC_DEV_HDR_MAGIC). 22916038816SMartin MatuskaIf there is an accounting error in the size or the number of L2ARC log blocks 230eda14cbcSMatt Macy.Nm Fl l 23116038816SMartin Matuskawill return 1. 23216038816SMartin MatuskaEach unique configuration is displayed only once. 233eda14cbcSMatt Macy.It Fl ll Ar device 23416038816SMartin MatuskaIn addition display label space usage stats. 23516038816SMartin MatuskaIf a valid L2ARC header was found 236eda14cbcSMatt Macyalso display the properties of log blocks used for restoring L2ARC contents 237eda14cbcSMatt Macy(persistent L2ARC). 238eda14cbcSMatt Macy.It Fl lll Ar device 23916038816SMartin MatuskaDisplay every configuration, unique or not. 24016038816SMartin MatuskaIf a valid L2ARC header was found 241eda14cbcSMatt Macyalso display the properties of log entries in log blocks used for restoring 242eda14cbcSMatt MacyL2ARC contents (persistent L2ARC). 243eda14cbcSMatt Macy.Pp 244eda14cbcSMatt MacyIf the 245eda14cbcSMatt Macy.Fl q 246eda14cbcSMatt Macyoption is also specified, don't print the labels or the L2ARC header. 247eda14cbcSMatt Macy.Pp 248eda14cbcSMatt MacyIf the 249eda14cbcSMatt Macy.Fl u 25016038816SMartin Matuskaoption is also specified, also display the uberblocks on this device. 25116038816SMartin MatuskaSpecify multiple times to increase verbosity. 252eda14cbcSMatt Macy.It Fl L 253eda14cbcSMatt MacyDisable leak detection and the loading of space maps. 254eda14cbcSMatt MacyBy default, 255eda14cbcSMatt Macy.Nm 256eda14cbcSMatt Macyverifies that all non-free blocks are referenced, which can be very expensive. 257eda14cbcSMatt Macy.It Fl m 258eda14cbcSMatt MacyDisplay the offset, spacemap, free space of each metaslab, all the log 259eda14cbcSMatt Macyspacemaps and their obsolete entry statistics. 260eda14cbcSMatt Macy.It Fl mm 261eda14cbcSMatt MacyAlso display information about the on-disk free space histogram associated with 262eda14cbcSMatt Macyeach metaslab. 263eda14cbcSMatt Macy.It Fl mmm 264eda14cbcSMatt MacyDisplay the maximum contiguous free space, the in-core free space histogram, and 265eda14cbcSMatt Macythe percentage of free space in each space map. 266eda14cbcSMatt Macy.It Fl mmmm 267eda14cbcSMatt MacyDisplay every spacemap record. 268eda14cbcSMatt Macy.It Fl M 269*681ce946SMartin MatuskaDisplay all "normal" vdev metaslab group information - per-vdev metaslab count, fragmentation, 270*681ce946SMartin Matuskaand free space histogram, as well as overall pool fragmentation and histogram. 271eda14cbcSMatt Macy.It Fl MM 272*681ce946SMartin Matuska"Special" vdevs are added to -M's normal output. 273eda14cbcSMatt Macy.It Fl O Ar dataset path 274eda14cbcSMatt MacyLook up the specified 275eda14cbcSMatt Macy.Ar path 276eda14cbcSMatt Macyinside of the 277eda14cbcSMatt Macy.Ar dataset 278eda14cbcSMatt Macyand display its metadata and indirect blocks. 279eda14cbcSMatt MacySpecified 280eda14cbcSMatt Macy.Ar path 281eda14cbcSMatt Macymust be relative to the root of 282eda14cbcSMatt Macy.Ar dataset . 283eda14cbcSMatt MacyThis option can be combined with 284eda14cbcSMatt Macy.Fl v 285eda14cbcSMatt Macyfor increasing verbosity. 286184c1b94SMartin Matuska.It Fl r Ar dataset path destination 287184c1b94SMartin MatuskaCopy the specified 288184c1b94SMartin Matuska.Ar path 289184c1b94SMartin Matuskainside of the 290184c1b94SMartin Matuska.Ar dataset 291184c1b94SMartin Matuskato the specified destination. 292184c1b94SMartin MatuskaSpecified 293184c1b94SMartin Matuska.Ar path 294184c1b94SMartin Matuskamust be relative to the root of 295184c1b94SMartin Matuska.Ar dataset . 296184c1b94SMartin MatuskaThis option can be combined with 297184c1b94SMartin Matuska.Fl v 298184c1b94SMartin Matuskafor increasing verbosity. 299eda14cbcSMatt Macy.It Xo 30016038816SMartin Matuska.Fl R Ar poolname vdev : Ns Ar offset : Ns Oo Ar lsize Ns / Oc Ns Ar psize Ns Op : Ns Ar flags 301eda14cbcSMatt Macy.Xc 302eda14cbcSMatt MacyRead and display a block from the specified device. 303eda14cbcSMatt MacyBy default the block is displayed as a hex dump, but see the description of the 304eda14cbcSMatt Macy.Sy r 305eda14cbcSMatt Macyflag, below. 306eda14cbcSMatt Macy.Pp 307eda14cbcSMatt MacyThe block is specified in terms of a colon-separated tuple 308eda14cbcSMatt Macy.Ar vdev 309eda14cbcSMatt Macy.Pq an integer vdev identifier 310eda14cbcSMatt Macy.Ar offset 311eda14cbcSMatt Macy.Pq the offset within the vdev 312eda14cbcSMatt Macy.Ar size 313eda14cbcSMatt Macy.Pq the physical size, or logical size / physical size 314eda14cbcSMatt Macyof the block to read and, optionally, 315eda14cbcSMatt Macy.Ar flags 316eda14cbcSMatt Macy.Pq a set of flags, described below . 317eda14cbcSMatt Macy.Pp 318eda14cbcSMatt Macy.Bl -tag -compact -width "b offset" 319eda14cbcSMatt Macy.It Sy b Ar offset 320eda14cbcSMatt MacyPrint block pointer at hex offset 321eda14cbcSMatt Macy.It Sy c 322eda14cbcSMatt MacyCalculate and display checksums 323eda14cbcSMatt Macy.It Sy d 32416038816SMartin MatuskaDecompress the block. 32516038816SMartin MatuskaSet environment variable 326eda14cbcSMatt Macy.Nm ZDB_NO_ZLE 327eda14cbcSMatt Macyto skip zle when guessing. 328eda14cbcSMatt Macy.It Sy e 329eda14cbcSMatt MacyByte swap the block 330eda14cbcSMatt Macy.It Sy g 331eda14cbcSMatt MacyDump gang block header 332eda14cbcSMatt Macy.It Sy i 333eda14cbcSMatt MacyDump indirect block 334eda14cbcSMatt Macy.It Sy r 335eda14cbcSMatt MacyDump raw uninterpreted block data 336eda14cbcSMatt Macy.It Sy v 337eda14cbcSMatt MacyVerbose output for guessing compression algorithm 338eda14cbcSMatt Macy.El 339eda14cbcSMatt Macy.It Fl s 340eda14cbcSMatt MacyReport statistics on 341eda14cbcSMatt Macy.Nm zdb 342eda14cbcSMatt MacyI/O. 343eda14cbcSMatt MacyDisplay operation counts, bandwidth, and error counts of I/O to the pool from 344eda14cbcSMatt Macy.Nm . 345eda14cbcSMatt Macy.It Fl S 346eda14cbcSMatt MacySimulate the effects of deduplication, constructing a DDT and then display 347eda14cbcSMatt Macythat DDT as with 348eda14cbcSMatt Macy.Fl DD . 349eda14cbcSMatt Macy.It Fl u 350eda14cbcSMatt MacyDisplay the current uberblock. 351eda14cbcSMatt Macy.El 352eda14cbcSMatt Macy.Pp 353eda14cbcSMatt MacyOther options: 354eda14cbcSMatt Macy.Bl -tag -width Ds 355eda14cbcSMatt Macy.It Fl A 356eda14cbcSMatt MacyDo not abort should any assertion fail. 357eda14cbcSMatt Macy.It Fl AA 358eda14cbcSMatt MacyEnable panic recovery, certain errors which would otherwise be fatal are 359eda14cbcSMatt Macydemoted to warnings. 360eda14cbcSMatt Macy.It Fl AAA 361eda14cbcSMatt MacyDo not abort if asserts fail and also enable panic recovery. 36216038816SMartin Matuska.It Fl e Oo Fl p Ar path Oc Ns … 363eda14cbcSMatt MacyOperate on an exported pool, not present in 364eda14cbcSMatt Macy.Pa /etc/zfs/zpool.cache . 365eda14cbcSMatt MacyThe 366eda14cbcSMatt Macy.Fl p 367eda14cbcSMatt Macyflag specifies the path under which devices are to be searched. 368eda14cbcSMatt Macy.It Fl x Ar dumpdir 369eda14cbcSMatt MacyAll blocks accessed will be copied to files in the specified directory. 370eda14cbcSMatt MacyThe blocks will be placed in sparse files whose name is the same as 371eda14cbcSMatt Macythat of the file or device read. 372eda14cbcSMatt Macy.Nm 373eda14cbcSMatt Macycan be then run on the generated files. 374eda14cbcSMatt MacyNote that the 375eda14cbcSMatt Macy.Fl bbc 376eda14cbcSMatt Macyflags are sufficient to access 377eda14cbcSMatt Macy.Pq and thus copy 378eda14cbcSMatt Macyall metadata on the pool. 379eda14cbcSMatt Macy.It Fl F 380eda14cbcSMatt MacyAttempt to make an unreadable pool readable by trying progressively older 381eda14cbcSMatt Macytransactions. 382eda14cbcSMatt Macy.It Fl G 383eda14cbcSMatt MacyDump the contents of the zfs_dbgmsg buffer before exiting 384eda14cbcSMatt Macy.Nm . 385eda14cbcSMatt Macyzfs_dbgmsg is a buffer used by ZFS to dump advanced debug information. 386eda14cbcSMatt Macy.It Fl I Ar inflight I/Os 387eda14cbcSMatt MacyLimit the number of outstanding checksum I/Os to the specified value. 388eda14cbcSMatt MacyThe default value is 200. 389eda14cbcSMatt MacyThis option affects the performance of the 390eda14cbcSMatt Macy.Fl c 391eda14cbcSMatt Macyoption. 39216038816SMartin Matuska.It Fl o Ar var Ns = Ns Ar value … 393eda14cbcSMatt MacySet the given global libzpool variable to the provided value. 394eda14cbcSMatt MacyThe value must be an unsigned 32-bit integer. 395eda14cbcSMatt MacyCurrently only little-endian systems are supported to avoid accidentally setting 396eda14cbcSMatt Macythe high 32 bits of 64-bit variables. 397eda14cbcSMatt Macy.It Fl P 39816038816SMartin MatuskaPrint numbers in an unscaled form more amenable to parsing, e.g.\& 39916038816SMartin Matuska.Sy 1000000 40016038816SMartin Matuskarather than 40116038816SMartin Matuska.Sy 1M . 402eda14cbcSMatt Macy.It Fl t Ar transaction 403eda14cbcSMatt MacySpecify the highest transaction to use when searching for uberblocks. 404eda14cbcSMatt MacySee also the 405eda14cbcSMatt Macy.Fl u 406eda14cbcSMatt Macyand 407eda14cbcSMatt Macy.Fl l 408eda14cbcSMatt Macyoptions for a means to see the available uberblocks and their associated 409eda14cbcSMatt Macytransaction numbers. 410eda14cbcSMatt Macy.It Fl U Ar cachefile 411eda14cbcSMatt MacyUse a cache file other than 412eda14cbcSMatt Macy.Pa /etc/zfs/zpool.cache . 413eda14cbcSMatt Macy.It Fl v 414eda14cbcSMatt MacyEnable verbosity. 415eda14cbcSMatt MacySpecify multiple times for increased verbosity. 416eda14cbcSMatt Macy.It Fl V 417eda14cbcSMatt MacyAttempt verbatim import. 418eda14cbcSMatt MacyThis mimics the behavior of the kernel when loading a pool from a cachefile. 419eda14cbcSMatt MacyOnly usable with 420eda14cbcSMatt Macy.Fl e . 421eda14cbcSMatt Macy.It Fl X 422eda14cbcSMatt MacyAttempt 423eda14cbcSMatt Macy.Qq extreme 424eda14cbcSMatt Macytransaction rewind, that is attempt the same recovery as 425eda14cbcSMatt Macy.Fl F 426eda14cbcSMatt Macybut read transactions otherwise deemed too old. 427eda14cbcSMatt Macy.It Fl Y 428eda14cbcSMatt MacyAttempt all possible combinations when reconstructing indirect split blocks. 429eda14cbcSMatt MacyThis flag disables the individual I/O deadman timer in order to allow as 430eda14cbcSMatt Macymuch time as required for the attempted reconstruction. 431eda14cbcSMatt Macy.It Fl y 432eda14cbcSMatt MacyPerform validation for livelists that are being deleted. 433eda14cbcSMatt MacyScans through the livelist and metaslabs, checking for duplicate entries 434eda14cbcSMatt Macyand compares the two, checking for potential double frees. 435eda14cbcSMatt MacyIf it encounters issues, warnings will be printed, but the command will not 436eda14cbcSMatt Macynecessarily fail. 437eda14cbcSMatt Macy.El 438eda14cbcSMatt Macy.Pp 439eda14cbcSMatt MacySpecifying a display option more than once enables verbosity for only that 440eda14cbcSMatt Macyoption, with more occurrences enabling more verbosity. 441eda14cbcSMatt Macy.Pp 442eda14cbcSMatt MacyIf no options are specified, all information about the named pool will be 443eda14cbcSMatt Macydisplayed at default verbosity. 44416038816SMartin Matuska. 445eda14cbcSMatt Macy.Sh EXAMPLES 446eda14cbcSMatt Macy.Bl -tag -width Ds 447eda14cbcSMatt Macy.It Xo 44816038816SMartin Matuska.Sy Example 1 : 449eda14cbcSMatt MacyDisplay the configuration of imported pool 45016038816SMartin Matuska.Ar rpool 451eda14cbcSMatt Macy.Xc 452eda14cbcSMatt Macy.Bd -literal 45316038816SMartin Matuska.No # Nm zdb Fl C Ar rpool 454eda14cbcSMatt MacyMOS Configuration: 455eda14cbcSMatt Macy version: 28 456eda14cbcSMatt Macy name: 'rpool' 45716038816SMartin Matuska … 458eda14cbcSMatt Macy.Ed 459eda14cbcSMatt Macy.It Xo 46016038816SMartin Matuska.Sy Example 2 : 461eda14cbcSMatt MacyDisplay basic dataset information about 46216038816SMartin Matuska.Ar rpool 463eda14cbcSMatt Macy.Xc 464eda14cbcSMatt Macy.Bd -literal 46516038816SMartin Matuska.No # Nm zdb Fl d Ar rpool 466eda14cbcSMatt MacyDataset mos [META], ID 0, cr_txg 4, 26.9M, 1051 objects 467eda14cbcSMatt MacyDataset rpool/swap [ZVOL], ID 59, cr_txg 356, 486M, 2 objects 46816038816SMartin Matuska … 469eda14cbcSMatt Macy.Ed 470eda14cbcSMatt Macy.It Xo 47116038816SMartin Matuska.Sy Example 3 : 472eda14cbcSMatt MacyDisplay basic information about object 0 in 47316038816SMartin Matuska.Ar rpool/export/home 474eda14cbcSMatt Macy.Xc 475eda14cbcSMatt Macy.Bd -literal 47616038816SMartin Matuska.No # Nm zdb Fl d Ar rpool/export/home 0 477eda14cbcSMatt MacyDataset rpool/export/home [ZPL], ID 137, cr_txg 1546, 32K, 8 objects 478eda14cbcSMatt Macy 479eda14cbcSMatt Macy Object lvl iblk dblk dsize lsize %full type 480eda14cbcSMatt Macy 0 7 16K 16K 15.0K 16K 25.00 DMU dnode 481eda14cbcSMatt Macy.Ed 482eda14cbcSMatt Macy.It Xo 48316038816SMartin Matuska.Sy Example 4 : 484eda14cbcSMatt MacyDisplay the predicted effect of enabling deduplication on 48516038816SMartin Matuska.Ar rpool 486eda14cbcSMatt Macy.Xc 487eda14cbcSMatt Macy.Bd -literal 48816038816SMartin Matuska.No # Nm zdb Fl S Ar rpool 489eda14cbcSMatt MacySimulated DDT histogram: 490eda14cbcSMatt Macy 491eda14cbcSMatt Macybucket allocated referenced 492eda14cbcSMatt Macy______ ______________________________ ______________________________ 493eda14cbcSMatt Macyrefcnt blocks LSIZE PSIZE DSIZE blocks LSIZE PSIZE DSIZE 494eda14cbcSMatt Macy------ ------ ----- ----- ----- ------ ----- ----- ----- 495eda14cbcSMatt Macy 1 694K 27.1G 15.0G 15.0G 694K 27.1G 15.0G 15.0G 496eda14cbcSMatt Macy 2 35.0K 1.33G 699M 699M 74.7K 2.79G 1.45G 1.45G 49716038816SMartin Matuska … 498eda14cbcSMatt Macydedup = 1.11, compress = 1.80, copies = 1.00, dedup * compress / copies = 2.00 499eda14cbcSMatt Macy.Ed 500eda14cbcSMatt Macy.El 50116038816SMartin Matuska. 502eda14cbcSMatt Macy.Sh SEE ALSO 503eda14cbcSMatt Macy.Xr zfs 8 , 504eda14cbcSMatt Macy.Xr zpool 8 505