Defragmentation is not working when a directory is supplied as the argument. When a file name is supplied as the argument, defragmentation works well. This can be demonstrated as follows: # mount /dev/sdb2 /mnt/btrfs # cd /mnt/btrfs/ # cp /usr/src/linux/fs/btrfs/zlib.c . (any suitable file will do, small text files seemed appropriate) # cp zlib.c fragmented-zlib.c # btrfs fi sync /mnt/btrfs # cat zlib.c >> fragmented-zlib.c # btrfs fi sync /mnt/btrfs # filefrag zlib.c fragmented-zlib.c zlib.c: 1 extent found fragmented-zlib.c: 2 extents found # btrfs filesystem defragment /mnt/btrfs/ # btrfs fi sync /mnt/btrfs # filefrag zlib.c fragmented-zlib.c zlib.c: 1 extent found fragmented-zlib.c: 2 extents found Now, supply a filename as the argument # btrfs filesystem defragment /mnt/btrfs/fragmented-zlib.c # btrfs fi sync /mnt/btrfs # filefrag zlib.c fragmented-zlib.c zlib.c: 1 extent found fragmented-zlib.c: 1 extent found I've also tested defragmentation on my normal btrfs filesystems, and have seen the same results. I've never seen a file defragmented when using a directory as the argument. Also, I was wondering if one of the Btrfs developers could clarify the intended scope of defragmentation when a directory is supplied as the argument. I have seen comments on the mailing list indicating that only the directory supplied is intended to be defragmented, and defragmentation will not recurse to subdirectories below. However, if I look at the code, and read the documentation for the older btrfsctl command (which seems to be the basis for the current btrfs command), it seems like the intention is to recursively defragment the entire tree below the directory supplied in the argument. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
