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diff --git a/cddl/contrib/opensolaris/cmd/zdb/zdb.8 b/cddl/contrib/opensolaris/cmd/zdb/zdb.8 new file mode 100644 index 0000000..e036b96 --- /dev/null +++ b/cddl/contrib/opensolaris/cmd/zdb/zdb.8 @@ -0,0 +1,306 @@ +'\" te +.\" Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. +.\" All Rights Reserved. +.\" +.\" This file and its contents are supplied under the terms of the +.\" Common Development and Distribution License ("CDDL"), version 1.0. +.\" You may only use this file in accordance with the terms of version +.\" 1.0 of the CDDL. +.\" +.\" A full copy of the text of the CDDL should have accompanied this +.\" source. A copy of the CDDL is also available via the Internet at +.\" http://www.illumos.org/license/CDDL. +.\" +.\" +.\" Copyright 2012, Richard Lowe. +.\" Copyright (c) 2012, Marcelo Araujo <araujo@FreeBSD.org>. +.\" All Rights Reserved. +.\" +.\" $FreeBSD$ +.\" +.Dd May 10, 2012 +.Dt ZDB 8 +.Os +.Sh NAME +.Nm zdb +.Nd Display zpool debugging and consistency information +.Sh SYNOPSIS +.Nm +.Op Fl CumdibcsDvhLXFPA +.Op Fl e Op Fl p Ar path... +.Op Fl t Ar txg +.Ar poolname +.Op Ar object ... +.Nm +.Op Fl divPA +.Op Fl e Op Fl p Ar path... +.Ar dataset +.Op Ar object ... +.Nm +.Fl m Op Fl LXFPA +.Op Fl t Ar txg +.Op Fl e Op Fl p Ar path... +.Ar poolname +.Nm +.Fl R Op Fl A +.Op Fl e Op Fl p Ar path... +.Ar poolname +.Ar vdev Ns : Ns Ar offset Ns : Ns Ar size Ns Op Ns : Ns Ar flags +.Nm +.Fl S +.Op Fl AP +.Op Fl e Op Fl p Ar path... +.Ar poolname +.Nm +.Fl l +.Op Fl uA +.Ar device +.Nm +.Fl C +.Op Fl A +.Op Fl U Ar cache +.Sh DESCRIPTION +The +.Nm +utility displays information about a ZFS pool useful for debugging and +performs some amount of consistency checking. +It is a not a general purpose tool and options (and facilities) may change. +This is neither a +.Xr fsck 8 +nor a +.Xr fsdb 8 +utility. +.Pp +The output of this command in general reflects the on-disk structure of a ZFS +pool, and is inherently unstable. +The precise output of most invocations is not documented, a knowledge of ZFS +internals is assumed. +.Pp +When operating on an imported and active pool it is possible, though unlikely, +that zdb may interpret inconsistent pool data and behave erratically. +.Sh OPTIONS +Display options: +.Bl -tag -width indent +.It Fl b +Display statistics regarding the number, size (logical, physical and +allocated) and deduplication of blocks. +.It Fl c +Verify the checksum of all metadata blocks while printing block statistics +(see +.Fl b Ns ). +.Pp +If specified multiple times, verify the checksums of all blocks. +.It Fl C +Display information about the configuration. If specified with no other +options, instead display information about the cache file +.Po Pa /etc/zfs/zpool.cache Pc . +To specify the cache file to display, see +.Fl U +.Pp +If specified multiple times, and a pool name is also specified display both +the cached configuration and the on-disk configuration. +If specified multiple times with +.Fl e +also display the configuration that would be used were the pool to be +imported. +.It Fl d +Display information about datasets. Specified once, displays basic dataset +information: ID, create transaction, size, and object count. +.Pp +If specified multiple times provides greater and greater verbosity. +.Pp +If object IDs are specified, display information about those specific objects only. +.It Fl D +Display deduplication statistics, including the deduplication ratio (dedup), +compression ratio (compress), inflation due to the zfs copies property +(copies), and an overall effective ratio (dedup * compress / copies). +.Pp +If specified twice, display a histogram of deduplication statistics, showing +the allocated (physically present on disk) and referenced (logically +referenced in the pool) block counts and sizes by reference count. +.It Fl h +Display pool history similar to +.Cm zpool history , +but include internal changes, transaction, and dataset information. +.It Fl i +Display information about intent log (ZIL) entries relating to each +dataset. +If specified multiple times, display counts of each intent log transaction +type. +.It Fl l Ar device +Display the vdev labels from the specified device. +If the +.Fl u +option is also specified, also display the uberblocks on this device. +.It Fl L +Disable leak tracing and the loading of space maps. +By default, +.Nm +verifies that all non-free blocks are referenced, which can be very expensive. +.It Fl m +Display the offset, spacemap, and free space of each metaslab. +When specified twice, also display information about the maximum contiguous +free space and the percentage of free space in each space map. +When specified three times display every spacemap record. +.It Xo +.Fl R Ar poolname +.Ar vdev Ns : Ns Ar offset Ns : Ns Ar size Ns Op Ns : Ns Ar flags +.Xc +Read and display a block from the specified device. By default the block is +displayed as a hex dump, but see the description of the +.Fl r +flag, below. +.Pp +The block is specified in terms of a colon-separated tuple +.Ar vdev +(an integer vdev identifier) +.Ar offset +(the offset within the vdev) +.Ar size +(the size of the block to read) and, optionally, +.Ar flags +(a set of flags, described below). +.Bl -tag -width indent +.It Sy b offset +Print block pointer +.It Sy d +Decompress the block +.It Sy e +Byte swap the block +.It Sy g +Dump gang block header +.It Sy i +Dump indirect block +.It Sy r +Dump raw uninterpreted block data +.El +.It Fl s +Report statistics on +.Nm Ns 's +I/O. +Display operation counts, bandwidth, and error counts of I/O to the pool from +.Nm . +.It Fl S +Simulate the effects of deduplication, constructing a DDT and then display +that DDT as with \fB-DD\fR. +.It Fl u +Display the current uberblock. +.El +.Pp +Other options: +.Bl -tag -width indent +.It Fl A +Do not abort should any assertion fail. +.It Fl AA +Enable panic recovery, certain errors which would otherwise be fatal are +demoted to warnings. +.It Fl AAA +Do not abort if asserts fail and also enable panic recovery. +.It Fl e Op Fl p Ar path... +Operate on an exported pool, not present in +.Pa /etc/zfs/zpool.cache . +The +.Fl p +flag specifies the path under which devices are to be searched. +.It Fl F +Attempt to make an unreadable pool readable by trying progressively older +transactions. +.It Fl P +Print numbers in an unscaled form more amenable to parsing, eg. 1000000 rather +than 1M. +.It Fl t Ar transaction +Specify the highest transaction to use when searching for uberblocks. +See also the +.Fl u +and +.Fl l +options for a means to see the available uberblocks and their associated +transaction numbers. +.It Fl U Ar cachefile +Use a cache file other than +.Pa /etc/zfs/zpool.cache . +This option is only valid with +.Fl C +.It Fl v +Enable verbosity. +Specify multiple times for increased verbosity. +.It Fl X +Attempt +.Ql extreme +transaction rewind, that is attempt the same recovery as +.Fl F +but read transactions otherwise deemed too old. +.El +.Pp +Specifying a display option more than once enables verbosity for only that +option, with more occurrences enabling more verbosity. +.Pp +If no options are specified, all information about the named pool will be +displayed at default verbosity. +.Sh EXAMPLES +.Bl -tag -width 0n +.It Sy Example 1 Display the configuration of imported pool 'rpool' +.Bd -literal -offset 2n +.Li # Ic zdb -C rpool + +MOS Configuration: + version: 28 + name: 'rpool' + ... +.Ed +.It Sy Example 2 Display basic dataset information about 'rpool' +.Bd -literal -offset 2n +.Li # Ic zdb -d rpool +Dataset mos [META], ID 0, cr_txg 4, 26.9M, 1051 objects +Dataset rpool/swap [ZVOL], ID 59, cr_txg 356, 486M, 2 objects + ... +.Ed +.It Xo Sy Example 3 Display basic information about object 0 in +.Sy 'rpool/export/home' +.Xc +.Bd -literal -offset 2n +.Li # Ic zdb -d rpool/export/home 0 +Dataset rpool/export/home [ZPL], ID 137, cr_txg 1546, 32K, 8 objects + + Object lvl iblk dblk dsize lsize %full type + 0 7 16K 16K 15.0K 16K 25.00 DMU dnode +.Ed +.It Xo Sy Example 4 Display the predicted effect of enabling deduplication on +.Sy 'rpool' +.Xc +.Bd -literal -offset 2n +.Li # Ic zdb -S rpool +Simulated DDT histogram: + +bucket allocated referenced +______ ______________________________ ______________________________ +refcnt blocks LSIZE PSIZE DSIZE blocks LSIZE PSIZE DSIZE +------ ------ ----- ----- ----- ------ ----- ----- ----- + 1 694K 27.1G 15.0G 15.0G 694K 27.1G 15.0G 15.0G + 2 35.0K 1.33G 699M 699M 74.7K 2.79G 1.45G 1.45G + ... +dedup = 1.11, compress = 1.80, copies = 1.00, dedup * compress / copies = 2.00 +.Ed +.El +.Sh SEE ALSO +.Xr zfs 8 , +.Xr zpool 8 +.Sh AUTHORS +This manual page is a +.Xr mdoc 7 +reimplementation of the +.Tn illumos +manual page +.Em zdb(1M) , +modified and customized for +.Fx +and licensed under the +Common Development and Distribution License +.Pq Tn CDDL . +.Pp +The +.Xr mdoc 7 +implementation of this manual page was initially written by +.An Martin Matuska Aq mm@FreeBSD.org +and +.An Marcelo Araujo Aq araujo@FreeBSD.org . |
