Chester wrote: > Kernel 3.1-rc8 > btrfs-progs-0.19 > mount options: noatime,autodefrag (space_cache is enabled) > There are snapshots present on the filesystem. > > When I do a btrfs fi defrag on a file, the file becomes much more > fragmented. The end result can be a file with 20k times more fragments > than before. Initially I thought the extents were just smaller but > were next to each other, so I checked with both 'filefrag' as well as > 'filefrag -v'. Both reported the same number. I don't know if this has > anything to do with having snapshots at all because files that haven't > been snapshotted yet are affected by this. Disk space isn't an issue > since my 1TB disk isn't even halfway filled, and moving the file > around actually gives me fairly contiguous files. Was any process doing heavy I/O work while you were defragging the file? Could you try to remount the fs without autodefrag, and defrag the file again? Firstly let's see if autodefrag makes things worse. -- 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
