'btrfs filesystem defrag' has an option '-t', whose manpage says "Any extent bigger than threshold given by -t option, will be considered already defragged. Use 0 to take the kernel default, and use 1 to say every single extent must be rewritten."
Here 'use 0' still works, it refers to the default value(256K), however, 'use 1' is an obvious typo, it should be -1, which means the largest value it can be. Right now, we use parse_size() which no more allow value '-1', so in order to keep the manpage correct, this updates it to only keep value '0'. If you want to make sure every single extent is rewritten, please use a fairly large size, say 1G. Reported-by: Sebastian Ochmann <ochm...@informatik.uni-bonn.de> Signed-off-by: Liu Bo <bo.li....@oracle.com> --- Documentation/btrfs-filesystem.txt | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/Documentation/btrfs-filesystem.txt b/Documentation/btrfs-filesystem.txt index 0ee79cb..c9c0b00 100644 --- a/Documentation/btrfs-filesystem.txt +++ b/Documentation/btrfs-filesystem.txt @@ -41,8 +41,7 @@ The start position and the number of bytes to defragment can be specified by start and len using '-s' and '-l' options below. Any extent bigger than threshold given by '-t' option, will be considered already defragged. -Use 0 to take the kernel default, and use 1 to -say every single extent must be rewritten. +Use 0 to take the kernel default. You can also turn on compression in defragment operations. + `Options` -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
