On Tue, Jan 03, 2012 at 03:34:43PM -0500, Ted Ts'o wrote: > On Sun, Jan 01, 2012 at 09:12:36PM +0100, Thomas Lindroth wrote: > > I ran e4defrag from e2fsprogs-1.42 on a file system and a lot of > > folders had their mtime updated as a result. This confuses both my > > backup program and myself. I guess the folder timestamps change > > because the temporary donor file is created in the same directory as > > the original file. XFS's defrag program put the donor files in a > > temporary folder in the root of the file system. Maybe e4defrag > > could do the same. > > Yes, that could be done if the user running the program (which does > not have to be root) has write access to the root directory of the > file system. There will certainly be cases where this will not be > true, however. xfs_fsr doesn't use these donor files to avoid mtime updates - it uses invisible IO (i.e. O_NOATIME|O_NOCMTIME) to do that. Also xfs_fsr needs root permissions because it uses the XFS open-by-handle interfaces. Indeed, it doesn't always use tmp donor dirs in the root directory - it only ever does that when doing an entire fs re-organisation. If you are just defragging a single file, it creates the tmp file in the same directory as the file being defragged... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
