I've observed several times that after a btrfs filesystem defrag a file was way more fragmented than before. For example, a file that was recently written, had 10 extents (output from filefrag). After a defrag filefrag showed more than 1900 extents. For curiosity, a simple copy of this "defragmented" file reduced the number of fragments to 1. With a different file I got 63 extents before and over 3000 extents after defrag. It's no problem if defrag can't reduce the fragmentation. But in this case it shouldn't be done at all.
regards, Johannes -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
