There are two "bg_reclaim_threshold" under the sysfs directory. One is at
/sys/fs/btrfs/<UUID>/ and sets the threshold to start the auto reclaim
thread. The other one is
at/sys/fs/btrfs/<UUID>/allocations/{data,metadata,system} and sets the
threshold to reclaim a block group.
These two options have the same name but they are calculated against
different metrics. The former is a percentage of allocated (for a device
extent) space on total device space, and the latter is a percentage of
reclaimable space on a block group's zone capacity.
Add description for per-space_info bg_reclaim_threshold to distinguish
these two same name configurations.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The copyright config variable can be used for a real copyright but we
don't have that for the manual pages and it was a stub. The date of page
generation time is added to the page anyway.
Signed-off-by: David Sterba <dsterba@suse.com>
This patch will add a dedicated section for btrfs sysfs interfaces.
It will include:
- Directory layout explanation
Including:
* Description
* Introduced in which kernel version
- Files explanation
Including:
* RW/RO type
* Description
* Introduced in which kernel version
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Per user report on https://old.reddit.com/r/btrfs/comments/107fnw1/btrfs_filesystem_mkswapfile_results_in_an/
the swapfile header does not contain the correct number of pages that
matches the file size and the activated swapfile is only 1GiB:
# btrfs filesystem mkswapfile -s 10g swapfile
# swapon swapfile
# cat /proc/swaps
Filename Type Size Used Priority
/swap/swapfile file 1048572 0 -2
A workaround is to run 'mkswap swapfile' before activation. Proper fix
is to calculate the number of (fixed size) 4K pages available for the
swap.
Issue: #568
Signed-off-by: David Sterba <dsterba@suse.com>
Add a command to create a new swapfile. The same can be achieved by
seandalone tools but they're just wrappers around the syscalls. The swap
format is simple enough to be created directly without mkswap command so
the swapfile can be created in one go.
The file must not exist before, this is to avoid problems with file
attributes or any other effects of existing extents. This also means the
command can't be used on block devices.
Default size is 2G, minimum size is 40KiB.
Signed-off-by: David Sterba <dsterba@suse.com>
A stale qgroup is level 0 and without a corresponding subvolume. There's
no convenient command for removing them and kernel does not remove them
automatically. Add a command so users don't have to parse and script the
output and/or delete them manually.
Signed-off-by: David Sterba <dsterba@suse.com>
The fact that the +C attribute excludes compression is mentioned in
<https://btrfs.readthedocs.io/en/latest/ch-compression.html#compatibility>.
Also mention it at the swapfile for clarity.
Pull-request: #530
Author: Nikolaos Chatzikonstantinou <nchatz314@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Adds a new options -W and --wait-norescan to wait for a rescan without
starting a new operation. This is useful for things like fstests where
we want do to do a "btrfs quota enable" and not continue until the
subsequent rescan has finished.
In addition to documenting the new option in the man page, clean up the
rescan entry to document the -w option a bit better.
Pull-request: #139
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The message could be confusing in case there's no send in progress and
the real reason is lack of permissions when deleting a subvolume.
Mention the permissions as first reason. Also update documentation.
Signed-off-by: David Sterba <dsterba@suse.com>
The option is listed among normal options but getopt does not recognize
it outside of experimental build, so make it consistent. Also mention
the correct version and need of the special build in documentation.
Signed-off-by: David Sterba <dsterba@suse.com>
As reported the documentation stated the send protocol v2 support was
supported since 5.18, but that's probably remnants of past revisions of
the patches introducing the support. Correct version is 6.0
Issue: #529
Signed-off-by: David Sterba <dsterba@suse.com>
Clarify that tree-stats can print inaccurate results or warnings when
the filesystem is mounted. Inspired by
https://bugzilla.kernel.org/show_bug.cgi?id=97481 .
Signed-off-by: David Sterba <dsterba@suse.com>
The leafsize has never been different from nodesize and since 4.0 (2015)
it's been alias for nodesize. This should be enough time for everybody
to update so the support is removed.
Signed-off-by: David Sterba <dsterba@suse.com>
The meaning of the -b/--byte-count option is different than what the
help text says. Historically it was used to set the filesystem size but
with multiple devices it sets the size on each device:
$ mkfs.btrfs /dev/sdx[1234]
...
Number of devices: 4
Devices:
ID SIZE PATH
1 2.00GiB /dev/sdx1
2 2.00GiB /dev/sdx2
3 2.00GiB /dev/sdx3
4 2.00GiB /dev/sdx4
And when set to 1G:
$ mkfs.btrfs -b 1G /dev/sdx[1234]
...
Number of devices: 4
Devices:
ID SIZE PATH
1 1.00GiB /dev/sdx1
2 1.00GiB /dev/sdx2
3 1.00GiB /dev/sdx3
4 1.00GiB /dev/sdx4
Signed-off-by: David Sterba <dsterba@suse.com>
RST format provides cross reference function that users can navigate
manual pages click. This patch is written by macro that replaces old
references to doc role in RST format.
Issue: #495
Signed-off-by: Sidong Yang <realwakka@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
swapon fails with an unclear error message, add some hints were to look
for more information.
Author: Torstein Eide
Pull-request: #491
Signed-off-by: David Sterba <dsterba@suse.com>
Mention the version support for the cross-mount support, since 5.18.
Author: AtticFinder65536
Pull-request: #480
Signed-off-by: David Sterba <dsterba@suse.com>
The size reported as Unallocated in the table was different that the one
in the listing, calculated differently. The values should reflect the
unallocated area available for the filesystem - not necessarily the
total size of the device. If there's such slack space it's reported
separately.
The values in the table mean:
- Unallocated: block device size - slack - allocated
- Total: block device size - slack
- Slack: block device size - filesystem
The new columns make the table wider but the values are deemed to be
important by users and for filesystems with normal profiles it fits
under reasonable line width. During balance or with multiple profiles it
can get wider but this should not be a serious problem.
Example output:
Overall:
Device size: 13.00GiB
Device allocated: 536.00MiB
Device unallocated: 12.48GiB
Device missing: 0.00B
Device slack: 1.00GiB
Used: 2.31MiB
Free (estimated): 12.48GiB (min: 6.24GiB)
Free (statfs, df): 12.48GiB
Data ratio: 1.00
Metadata ratio: 2.00
Global reserve: 3.50MiB (used: 0.00B)
Multiple profiles: no
Data Metadata System
Id Path single DUP DUP Unallocated Total Slack
-- ---------- ------- --------- -------- ----------- -------- -------
1 /dev/loop0 8.00MiB 512.00MiB 16.00MiB 2.48GiB 3.00GiB 1.00GiB
2 /dev/loop1 - - - 10.00GiB 10.00GiB -
-- ---------- ------- --------- -------- ----------- -------- -------
Total 8.00MiB 256.00MiB 8.00MiB 12.48GiB 13.00GiB 1.00GiB
Used 2.00MiB 144.00KiB 16.00KiB
Issue: #508
Pull-request: #509 (partial fix)
Signed-off-by: David Sterba <dsterba@suse.com>
The new '-b' option will be responsible for converting to block group
tree compat ro feature.
The workflow looks like this for new convert:
- Setting CHANGING_BG_TREE flag
And initialize fs_info->last_converted_bg_bytenr value to (u64)-1.
Any bg with bytenr >= last_converted_bg_bytenr will have its bg item
update go to the new root (bg tree).
- Iterate each block group by their bytenr in descending order
This involves:
* Delete the old bg item from the old tree (extent tree)
* Update last_converted_bg_bytenr to the bytenr of the bg
* Add the new bg item into the new tree (bg tree)
* If we have converted a bunch of bgs, commit current transaction
- Clear CHANGING_BG_TREE flag
And set the new BLOCK_GROUP_TREE compat ro flag and commit.
And since we're doing the convert in multiple transactions, we also need
to resume from last interrupted convert.
In that case, we just grab the last unconverted bg, and start from it.
And to co-operate with the new kernel requirement for both no-holes and
free-space-tree features, the convert tool will check for
free-space-tree feature. If not enabled, will error out with an error
message to how to continue (by mounting with "-o space_cache=v2").
For missing no-holes feature, we just need to set the flag during
convert.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The command group of 'replace' belongs to device and could be seen as
confusing. At minimum we can add an alias so now there's equivalent:
# btrfs replace start
# btrfs device replace start
Both commands will exist for backward compatibility, tough we might
revisit which one is the primary one.
Issue: #484
Signed-off-by: David Sterba <dsterba@suse.com>
Copy contents from https://btrfs.wiki.kernel.org/index.php/Changelog#By_feature
The formatting is done by a definition and list, instead of a table.
Unfortunatelly RST does not wrap long text in table cells so the width
exceeds visible area.
Signed-off-by: David Sterba <dsterba@suse.com>
