Manpage/btrfs-filesystem

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=btrfs-filesystem(8) manual page=
 
 
{{GeneratedManpage
 
{{GeneratedManpage
 
|name=btrfs-filesystem}}
 
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==NAME==
 
btrfs-filesystem - command group that primarily does work on the whole filesystems
 
 
==SYNOPSIS==
 
 
<p><b>btrfs filesystem</b> <em>&lt;subcommand&gt;</em> <em>&lt;args&gt;</em></p>
 
==DESCRIPTION==
 
 
<p><b>btrfs filesystem</b> is used to perform several whole filesystem level tasks,
 
including all the regular filesystem operations like resizing, space stats,
 
label setting/getting, and defragmentation. There are other whole filesystem
 
tasks like scrub or balance that are grouped in separate commands.</p>
 
==SUBCOMMAND==
 
 
<dl>
 
<dt>
 
<b>df</b> [options] <em>&lt;path&gt;</em>
 
<dd>
 
<p>
 
Show a terse summary information about allocation of block group types of a given
 
mount point. The original purpose of this command was a debugging helper. The
 
output needs to be further interpreted and is not suitable for quick overview.
 
</p>
 
<div>
 
<p>An example with description:</p>
 
<ul>
 
<li>
 
<p>
 
device size: <em>1.9TiB</em>, one device, no RAID
 
</p>
 
</li>
 
<li>
 
<p>
 
filesystem size: <em>1.9TiB</em>
 
</p>
 
</li>
 
<li>
 
<p>
 
created with: <em>mkfs.btrfs -d single -m single</em>
 
</p>
 
</li>
 
</ul>
 
</div>
 
<pre>$ btrfs filesystem df /path
 
Data, single: total=1.15TiB, used=1.13TiB
 
System, single: total=32.00MiB, used=144.00KiB
 
Metadata, single: total=12.00GiB, used=6.45GiB
 
GlobalReserve, single: total=512.00MiB, used=0.00B</pre>
 
<div>
 
<ul>
 
<li>
 
<p>
 
<em>Data</em>, <em>System</em> and <em>Metadata</em> are separate block group types.
 
<em>GlobalReserve</em> is an artificial and internal emergency space, see below.
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>single</em>&#8201;&#8212;&#8201;the allocation profile, defined at mkfs time
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>total</em>&#8201;&#8212;&#8201;sum of space reserved for
 
all allocation profiles of the given type, ie. all Data/single. Note that it&#8217;s
 
not total size of filesystem.
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>used</em>&#8201;&#8212;&#8201;sum of used space of the above, ie. file extents, metadata blocks
 
</p>
 
</li>
 
</ul>
 
</div>
 
<p><em>GlobalReserve</em> is an artificial and internal emergency space. It is used eg.
 
when the filesystem is full. Its <em>total</em> size is dynamic based on the
 
filesystem size, usually not larger than 512MiB, <em>used</em> may fluctuate.</p>
 
<p>The GlobalReserve is a portion of Metadata. In case the filesystem metadata is
 
exhausted, <em>GlobalReserve/total + Metadata/used = Metadata/total</em>. Otherwise
 
there appears to be some unused space of Metadata.</p>
 
<p><tt>Options</tt></p>
 
<dl>
 
<dt>
 
-b|--raw
 
<dd>
 
<p>
 
raw numbers in bytes, without the <em>B</em> suffix
 
</p>
 
 
<dt>
 
-h|--human-readable
 
<dd>
 
<p>
 
print human friendly numbers, base 1024, this is the default
 
</p>
 
 
<dt>
 
-H
 
<dd>
 
<p>
 
print human friendly numbers, base 1000
 
</p>
 
 
<dt>
 
--iec
 
<dd>
 
<p>
 
select the 1024 base for the following options, according to the IEC standard
 
</p>
 
 
<dt>
 
--si
 
<dd>
 
<p>
 
select the 1000 base for the following options, according to the SI standard
 
</p>
 
 
<dt>
 
-k|--kbytes
 
<dd>
 
<p>
 
show sizes in KiB, or kB with --si
 
</p>
 
 
<dt>
 
-m|--mbytes
 
<dd>
 
<p>
 
show sizes in MiB, or MB with --si
 
</p>
 
 
<dt>
 
-g|--gbytes
 
<dd>
 
<p>
 
show sizes in GiB, or GB with --si
 
</p>
 
 
<dt>
 
-t|--tbytes
 
<dd>
 
<p>
 
show sizes in TiB, or TB with --si
 
</p>
 
<p>If conflicting options are passed, the last one takes precedence.</p>
 
 
</dl>
 
 
<dt>
 
<b>defragment</b> [options] <em>&lt;file&gt;</em>|<em>&lt;dir&gt;</em> [<em>&lt;file&gt;</em>|<em>&lt;dir&gt;</em>&#8230;]
 
<dd>
 
<p>
 
Defragment file data on a mounted filesystem. Requires kernel 2.6.33 and newer.
 
</p>
 
<p>If <em>-r</em> is passed, files in dir will be defragmented recursively (not
 
descending to subvolumes, mount points and directory symlinks).
 
The start position and the number of bytes to defragment can be specified by
 
start and length using <em>-s</em> and <em>-l</em> options below.
 
Extents bigger than value given by <em>-t</em> will be skipped, otherwise this value
 
is used as a target extent size, but is only advisory and may not be reached
 
if the free space is too fragmented.
 
Use 0 to take the kernel default, which is 256kB but may change in the future.
 
You can also turn on compression in defragment operations.</p>
 
<blockquote><b>Warning:</b>
 
Defragmenting with Linux kernel versions &lt; 3.9 or ≥ 3.14-rc2 as well as
 
with Linux stable kernel versions ≥ 3.10.31, ≥ 3.12.12 or ≥ 3.13.4 will break up
 
the reflinks of COW data (for example files copied with <tt>cp --reflink</tt>,
 
snapshots or de-duplicated data).
 
This may cause considerable increase of space usage depending on the broken up
 
reflinks.</blockquote>
 
<blockquote><b>Note:</b>
 
Directory arguments without <em>-r</em> do not defragment files recursively but will
 
defragment certain internal trees (extent tree and the subvolume tree). This has been
 
confusing and could be removed in the future.</blockquote>
 
<p>For <em>start</em>, <em>len</em>, <em>size</em> it is possible to append
 
units designator: 'K', 'M', 'G', 'T', 'P', or 'E', which represent
 
KiB, MiB, GiB, TiB, PiB, or EiB, respectively (case does not matter).</p>
 
<p><tt>Options</tt></p>
 
<dl>
 
<dt>
 
-c[<em>&lt;algo&gt;</em>]
 
<dd>
 
<p>
 
compress file contents while defragmenting. Optional argument selects the compression
 
algorithm, <em>zlib</em> (default), <em>lzo</em> or <em>zstd</em>. Currently it&#8217;s not possible to select no
 
compression. See also section <em>EXAMPLES</em>.
 
</p>
 
 
<dt>
 
-r
 
<dd>
 
<p>
 
defragment files recursively in given directories, does not descend to
 
subvolumes or mount points
 
</p>
 
 
<dt>
 
-f
 
<dd>
 
<p>
 
flush data for each file before going to the next file.
 
</p>
 
<p>This will limit the amount of dirty data to current file, otherwise the amount
 
accumulates from several files and will increase system load. This can also lead
 
to ENOSPC if there&#8217;s too much dirty data to write and it&#8217;s not possible to make
 
the reservations for the new data (ie. how the COW design works).</p>
 
 
<dt>
 
-s <em>&lt;start&gt;</em>[kKmMgGtTpPeE]
 
<dd>
 
<p>
 
defragmentation will start from the given offset, default is beginning of a file
 
</p>
 
 
<dt>
 
-l <em>&lt;len&gt;</em>[kKmMgGtTpPeE]
 
<dd>
 
<p>
 
defragment only up to <em>len</em> bytes, default is the file size
 
</p>
 
 
<dt>
 
-t <em>&lt;size&gt;</em>[kKmMgGtTpPeE]
 
<dd>
 
<p>
 
target extent size, do not touch extents bigger than <em>size</em>, default: 32M
 
</p>
 
<p>The value is only advisory and the final size of the extents may differ,
 
depending on the state of the free space and fragmentation or other internal
 
logic. Reasonable values are from tens to hundreds of megabytes.</p>
 
 
<dt>
 
-v
 
<dd>
 
<p>
 
(deprecated) alias for global <em>-v</em> option
 
</p>
 
 
</dl>
 
 
<dt>
 
<b>du</b> [options] <em>&lt;path&gt;</em> [<em>&lt;path&gt;</em>..]
 
<dd>
 
<p>
 
Calculate disk usage of the target files using FIEMAP. For individual
 
files, it will report a count of total bytes, and exclusive (not
 
shared) bytes. We also calculate a <em>set shared</em> value which is
 
described below.
 
</p>
 
<p>Each argument to <em>btrfs filesystem du</em> will have a <em>set shared</em> value
 
calculated for it. We define each <em>set</em> as those files found by a
 
recursive search of an argument (recursion descends to subvolumes but not
 
mount points). The <em>set shared</em> value then is a sum of all shared space
 
referenced by the set.</p>
 
<p><em>set shared</em> takes into account overlapping shared extents, hence it
 
isn&#8217;t as simple as adding up shared extents.</p>
 
<p><tt>Options</tt></p>
 
<dl>
 
<dt>
 
-s|--summarize
 
<dd>
 
<p>
 
display only a total for each argument
 
</p>
 
 
<dt>
 
--raw
 
<dd>
 
<p>
 
raw numbers in bytes, without the <em>B</em> suffix.
 
</p>
 
 
<dt>
 
--human-readable
 
<dd>
 
<p>
 
print human friendly numbers, base 1024, this is the default
 
</p>
 
 
<dt>
 
--iec
 
<dd>
 
<p>
 
select the 1024 base for the following options, according to the IEC standard.
 
</p>
 
 
<dt>
 
--si
 
<dd>
 
<p>
 
select the 1000 base for the following options, according to the SI standard.
 
</p>
 
 
<dt>
 
--kbytes
 
<dd>
 
<p>
 
show sizes in KiB, or kB with --si.
 
</p>
 
 
<dt>
 
--mbytes
 
<dd>
 
<p>
 
show sizes in MiB, or MB with --si.
 
</p>
 
 
<dt>
 
--gbytes
 
<dd>
 
<p>
 
show sizes in GiB, or GB with --si.
 
</p>
 
 
<dt>
 
--tbytes
 
<dd>
 
<p>
 
show sizes in TiB, or TB with --si.
 
</p>
 
 
</dl>
 
 
<dt>
 
<b>label</b> [<em>&lt;device&gt;</em>|<em>&lt;mountpoint&gt;</em>] [<em>&lt;newlabel&gt;</em>]
 
<dd>
 
<p>
 
Show or update the label of a filesystem. This works on a mounted filesystem or
 
a filesystem image.
 
</p>
 
<p>The <em>newlabel</em> argument is optional. Current label is printed if the argument
 
is omitted.</p>
 
<blockquote><b>Note:</b>
 
the maximum allowable length shall be less than 256 chars and must not contain
 
a newline. The trailing newline is stripped automatically.</blockquote>
 
 
</dl>
 
<dl>
 
<dt>
 
<b>resize</b> [options] [<em>&lt;devid&gt;</em>:][+/-]<em>&lt;size&gt;</em>[kKmMgGtTpPeE]|[<em>&lt;devid&gt;</em>:]max <em>&lt;path&gt;</em>
 
<dd>
 
<p>
 
Resize a mounted filesystem identified by <em>path</em>. A particular device
 
can be resized by specifying a <em>devid</em>.
 
</p>
 
<blockquote><b>Warning:</b>
 
If <em>path</em> is a file containing a BTRFS image then resize does not work
 
as expected and does not resize the image. This would resize the underlying
 
filesystem instead.</blockquote>
 
<p>The <em>devid</em> can be found in the output of <b>btrfs filesystem show</b> and
 
defaults to 1 if not specified.
 
The <em>size</em> parameter specifies the new size of the filesystem.
 
If the prefix <em>+</em> or <em>-</em> is present the size is increased or decreased
 
by the quantity <em>size</em>.
 
If no units are specified, bytes are assumed for <em>size</em>.
 
Optionally, the size parameter may be suffixed by one of the following
 
unit designators: 'K', 'M', 'G', 'T', 'P', or 'E', which represent
 
KiB, MiB, GiB, TiB, PiB, or EiB, respectively (case does not matter).</p>
 
<p>If <em>max</em> is passed, the filesystem will occupy all available space on the
 
device respecting <em>devid</em> (remember, devid 1 by default).</p>
 
<p>The resize command does not manipulate the size of underlying
 
partition.  If you wish to enlarge/reduce a filesystem, you must make sure you
 
can expand the partition before enlarging the filesystem and shrink the
 
partition after reducing the size of the filesystem.  This can done using
 
[http://man7.org/linux/man-pages/man8/fdisk.8.html fdisk(8)] or [http://man7.org/linux/man-pages/man8/parted.8.html parted(8)] to delete the existing partition and recreate
 
it with the new desired size.  When recreating the partition make sure to use
 
the same starting partition offset as before.</p>
 
<p>Growing is usually instant as it only updates the size. However, shrinking could
 
take a long time if there are data in the device area that&#8217;s beyond the new
 
end. Relocation of the data takes time.</p>
 
<p>See also section <em>EXAMPLES</em>.</p>
 
<p><tt>Options</tt></p>
 
<dl>
 
<dt>
 
--enqueue
 
<dd>
 
<p>
 
wait if there&#8217;s another exclusive operation running, otherwise continue
 
</p>
 
 
</dl>
 
 
<dt>
 
<b>show</b> [options] [<em>&lt;path&gt;</em>|<em>&lt;uuid&gt;</em>|<em>&lt;device&gt;</em>|<em>&lt;label&gt;</em>]
 
<dd>
 
<p>
 
Show the btrfs filesystem with some additional info about devices and space
 
allocation.
 
</p>
 
<p>If no option none of <em>path</em>/<em>uuid</em>/<em>device</em>/<em>label</em> is passed, information
 
about all the BTRFS filesystems is shown, both mounted and unmounted.</p>
 
<p><tt>Options</tt></p>
 
<dl>
 
<dt>
 
-m|--mounted
 
<dd>
 
<p>
 
probe kernel for mounted BTRFS filesystems
 
</p>
 
 
<dt>
 
-d|--all-devices
 
<dd>
 
<p>
 
scan all devices under /dev, otherwise the devices list is extracted from the
 
/proc/partitions file. This is a fallback option if there&#8217;s no device node
 
manager (like udev) available in the system.
 
</p>
 
 
<dt>
 
--raw
 
<dd>
 
<p>
 
raw numbers in bytes, without the <em>B</em> suffix
 
</p>
 
 
<dt>
 
--human-readable
 
<dd>
 
<p>
 
print human friendly numbers, base 1024, this is the default
 
</p>
 
 
<dt>
 
--iec
 
<dd>
 
<p>
 
select the 1024 base for the following options, according to the IEC standard
 
</p>
 
 
<dt>
 
--si
 
<dd>
 
<p>
 
select the 1000 base for the following options, according to the SI standard
 
</p>
 
 
<dt>
 
--kbytes
 
<dd>
 
<p>
 
show sizes in KiB, or kB with --si
 
</p>
 
 
<dt>
 
--mbytes
 
<dd>
 
<p>
 
show sizes in MiB, or MB with --si
 
</p>
 
 
<dt>
 
--gbytes
 
<dd>
 
<p>
 
show sizes in GiB, or GB with --si
 
</p>
 
 
<dt>
 
--tbytes
 
<dd>
 
<p>
 
show sizes in TiB, or TB with --si
 
</p>
 
 
</dl>
 
 
<dt>
 
<b>sync</b> <em>&lt;path&gt;</em>
 
<dd>
 
<p>
 
Force a sync of the filesystem at <em>path</em>, similar to the [http://man7.org/linux/man-pages/man1/sync.1.html sync(1)] command. In
 
addition, it starts cleaning of deleted subvolumes. To wait for the subvolume
 
deletion to complete use the <b>btrfs subvolume sync</b> command.
 
</p>
 
 
<dt>
 
<b>usage</b> [options] <em>&lt;path&gt;</em> [<em>&lt;path&gt;</em>&#8230;]
 
<dd>
 
<p>
 
Show detailed information about internal filesystem usage. This is supposed to
 
replace the <b>btrfs filesystem df</b> command in the long run.
 
</p>
 
<p>The level of detail can differ if the command is run under a regular or the
 
root user (due to use of restricted ioctl). For both there&#8217;s a summary section
 
with information about space usage:</p>
 
<pre>$ btrfs filesystem usage /path
 
WARNING: cannot read detailed chunk info, RAID5/6 numbers will be incorrect, run as root
 
Overall:
 
    Device size:                  1.82TiB
 
    Device allocated:              1.17TiB
 
    Device unallocated:          669.99GiB
 
    Device missing:                  0.00B
 
    Used:                          1.14TiB
 
    Free (estimated):            692.57GiB      (min: 692.57GiB)
 
    Free (statfs, df)            692.57GiB
 
    Data ratio:                      1.00
 
    Metadata ratio:                  1.00
 
    Global reserve:              512.00MiB      (used: 0.00B)
 
    Multiple profiles:                  no</pre>
 
<div>
 
<ul>
 
<li>
 
<p>
 
<em>Device size</em>&#8201;&#8212;&#8201;sum of raw device capacity available to the filesystem
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Device allocated</em>&#8201;&#8212;&#8201;sum of total space allocated for data/metadata/system
 
profiles, this also accounts space reserved but not yet used for extents
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Device unallocated</em>&#8201;&#8212;&#8201;the remaining unallocated space for future
 
allocations (difference of the above two numbers)
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Device missing</em>&#8201;&#8212;&#8201;sum of capacity of all missing devices
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Used</em>&#8201;&#8212;&#8201;sum of the used space of data/metadata/system profiles, not
 
including the reserved space
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Free (estimated)</em>&#8201;&#8212;&#8201;approximate size of the remaining free space usable for
 
data, including currently allocated space and estimating the usage of the
 
unallocated space based on the block group profiles, the <em>min</em> is the lower bound
 
of the estimate in case multiple profiles are present
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Free (statfs, df)</em>&#8201;&#8212;&#8201;the amount of space available for data as reported by the
 
<tt>statfs</tt> syscall, also returned as <em>Avail</em> in the output of <em>df</em>. The value is
 
calculated in a different way and may not match the estimate in some cases (eg.
 
multiple profiles).
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Data ratio</em>&#8201;&#8212;&#8201;ratio of total space for data including redundancy or parity to
 
the effectively usable data space, eg. single is 1.0, RAID1 is 2.0 and for RAID5/6
 
it depends on the number of devices
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Metadata ratio</em>&#8201;&#8212;&#8201;dtto, for metadata
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Global reserve</em>&#8201;&#8212;&#8201;portion of metadata currently used for global block
 
reserve, used for emergency purposes (like deletion on a full filesystem)
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Multiple profiles</em>&#8201;&#8212;&#8201;what block group types (data, metadata) have more than
 
one profile (single, raid1, &#8230;), see [[Manpage/btrfs|btrfs(5)]]
 
section <em>FILESYSTEMS WITH MULTIPLE BLOCK GROUP PROFILES</em>.
 
</p>
 
</li>
 
</ul>
 
</div>
 
<p>And on a zoned filesystem there are two more lines in the <em>Device</em> section:</p>
 
<pre>    Device zone unusable:          5.13GiB
 
    Device zone size:            256.00MiB</pre>
 
<div>
 
<ul>
 
<li>
 
<p>
 
<em>Device zone unusable</em>&#8201;&#8212;&#8201;sum of of space that&#8217;s been used in the past
 
but now is not due to COW and not referenced anymory, the chunks have to
 
be reclaimed and zones reset to make it usable again
 
</p>
 
</li>
 
<li>
 
<p>
 
<em>Device zone size</em>&#8201;&#8212;&#8201;the reported zone size of the host-managed device, same
 
for all devices
 
</p>
 
</li>
 
</ul>
 
</div>
 
<p>The root user will also see stats broken down by block group types:</p>
 
<pre>Data,single: Size:1.15TiB, Used:1.13TiB (98.26%)
 
  /dev/sdb        1.15TiB
 
 
Metadata,single: Size:12.00GiB, Used:6.45GiB (53.75%)
 
  /dev/sdb      12.00GiB
 
 
System,single: Size:32.00MiB, Used:144.00KiB (0.44%)
 
  /dev/sdb      32.00MiB
 
 
Unallocated:
 
  /dev/sdb      669.99GiB</pre>
 
<p><em>Data</em> is block group type, <em>single</em> is block group profile, <em>Size</em> is total
 
size occupied by this type, <em>Used</em> is the actually used space, the percent is
 
ratio of <em>Used/Size</em>. The <em>Unallocated</em> is remaining space.</p>
 
<p><tt>Options</tt></p>
 
<dl>
 
<dt>
 
-b|--raw
 
<dd>
 
<p>
 
raw numbers in bytes, without the <em>B</em> suffix
 
</p>
 
 
<dt>
 
-h|--human-readable
 
<dd>
 
<p>
 
print human friendly numbers, base 1024, this is the default
 
</p>
 
 
<dt>
 
-H
 
<dd>
 
<p>
 
print human friendly numbers, base 1000
 
</p>
 
 
<dt>
 
--iec
 
<dd>
 
<p>
 
select the 1024 base for the following options, according to the IEC standard
 
</p>
 
 
<dt>
 
--si
 
<dd>
 
<p>
 
select the 1000 base for the following options, according to the SI standard
 
</p>
 
 
<dt>
 
-k|--kbytes
 
<dd>
 
<p>
 
show sizes in KiB, or kB with --si
 
</p>
 
 
<dt>
 
-m|--mbytes
 
<dd>
 
<p>
 
show sizes in MiB, or MB with --si
 
</p>
 
 
<dt>
 
-g|--gbytes
 
<dd>
 
<p>
 
show sizes in GiB, or GB with --si
 
</p>
 
 
<dt>
 
-t|--tbytes
 
<dd>
 
<p>
 
show sizes in TiB, or TB with --si
 
</p>
 
 
<dt>
 
-T
 
<dd>
 
<p>
 
show data in tabular format
 
</p>
 
<p>If conflicting options are passed, the last one takes precedence.</p>
 
 
</dl>
 
 
</dl>
 
==EXAMPLES==
 
 
<p><b>$ btrfs filesystem defrag -v -r dir/</b></p>
 
<p>Recursively defragment files under <em>dir/</em>, print files as they are processed.
 
The file names will be printed in batches, similarly the amount of data triggered
 
by defragmentation will be proportional to last N printed files. The system dirty
 
memory throttling will slow down the defragmentation but there can still be a lot
 
of IO load and the system may stall for a moment.</p>
 
<p><b>$ btrfs filesystem defrag -v -r -f dir/</b></p>
 
<p>Recursively defragment files under <em>dir/</em>, be verbose and wait until all blocks
 
are flushed before processing next file. You can note slower progress of the
 
output and lower IO load (proportional to currently defragmented file).</p>
 
<p><b>$ btrfs filesystem defrag -v -r -f -clzo dir/</b></p>
 
<p>Recursively defragment files under <em>dir/</em>, be verbose, wait until all blocks are
 
flushed and force file compression.</p>
 
<p><b>$ btrfs filesystem defrag -v -r -t 64M dir/</b></p>
 
<p>Recursively defragment files under <em>dir/</em>, be verbose and try to merge extents
 
to be about 64MiB. As stated above, the success rate depends on actual free
 
space fragmentation and the final result is not guaranteed to meet the target
 
even if run repeatedly.</p>
 
<p><b>$ btrfs filesystem resize -1G /path</b></p>
 
<p><b>$ btrfs filesystem resize 1:-1G /path</b></p>
 
<p>Shrink size of the filesystem&#8217;s device id 1 by 1GiB. The first syntax expects a
 
device with id 1 to exist, otherwise fails. The second is equivalent and more
 
explicit. For a single-device filesystem it&#8217;s typically not necessary to
 
specify the devid though.</p>
 
<p><b>$ btrfs filesystem resize max /path</b></p>
 
<p><b>$ btrfs filesystem resize 1:max /path</b></p>
 
<p>Let&#8217;s assume that devid 1 exists and the filesystem does not occupy the whole
 
block device, eg. it has been enlarged and we want to grow the filesystem. By
 
simply using <em>max</em> as size we will achieve that.</p>
 
<blockquote><b>Note:</b>
 
There are two ways to minimize the filesystem on a given device. The
 
<b>btrfs inspect-internal min-dev-size</b> command, or iteratively shrink in steps.</blockquote>
 
==EXIT STATUS==
 
 
<p><b>btrfs filesystem</b> returns a zero exit status if it succeeds. Non zero is
 
returned in case of failure.</p>
 
==AVAILABILITY==
 
 
<p><b>btrfs</b> is part of btrfs-progs.
 
Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for
 
further details.</p>
 
==SEE ALSO==
 
 
<p>[[Manpage/btrfs-subvolume|btrfs-subvolume(8)]],
 
[[Manpage/mkfs.btrfs|mkfs.btrfs(8)]],</p>
 
[[Category:Manpage]]
 

Latest revision as of 12:29, 12 January 2022

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