diff options
| author | David Sterba <dsterba@suse.com> | 2016-07-28 13:14:08 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2016-07-28 14:08:30 +0200 |
| commit | 2f732723d6c1e3b6e9205e96da4c600ee72de875 (patch) | |
| tree | 5eafd136b2353a773bbd08b63af8ac2c49752ae9 /Documentation/btrfs-filesystem.asciidoc | |
| parent | 2542112e0ce4558ea7cf2d27104469c5e3709f4e (diff) | |
btrfs-progs: fi defrag: change default extent target size to 32 MiB
The kernel default is too low, 32 MiB is recommended and should give
better results.
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'Documentation/btrfs-filesystem.asciidoc')
| -rw-r--r-- | Documentation/btrfs-filesystem.asciidoc | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/Documentation/btrfs-filesystem.asciidoc b/Documentation/btrfs-filesystem.asciidoc index 8fb15eac..9782af9b 100644 --- a/Documentation/btrfs-filesystem.asciidoc +++ b/Documentation/btrfs-filesystem.asciidoc @@ -117,15 +117,23 @@ compression. See also section 'EXAMPLES'. -r:::: defragment files recursively in given directories -f:::: -flush data for each file before going to the next file. This will limit the amount -of dirty data to current file, otherwise the amount cumulates from several files -and may increase system load. +flush data for each file before going to the next file. ++ +This will limit the amount of dirty data to current file, otherwise the amount +cumulates from several files and will increase system load. This can also lead +to ENOSPC if there's too much dirty data to write and it's not possible to make +the reservations for the new data (ie. how the COW design works). ++ -s <start>[kKmMgGtTpPeE]:::: defragmentation will start from the given offset, default is beginning of a file -l <len>[kKmMgGtTpPeE]:::: defragment only up to 'len' bytes, default is the file size -t <size>[kKmMgGtTpPeE]:::: -target extent size, do not touch extents bigger than 'size' +target extent size, do not touch extents bigger than 'size', default: 32M ++ +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. *du* [options] <path> [<path>..]:: Calculate disk usage of the target files using FIEMAP. For individual |