On Fri, May 01, 2015 at 10:31:47AM -0400, Theodore Ts'o wrote: > On Thu, Apr 30, 2015 at 10:02:58PM -0700, Christian Kujau wrote: > > Notice the "18M" entry for "." - I realize this is a directory for > > temporary files, meaning that lots of files are generated here, but > > the server is not _that_ busy; according to lsof(8) no files are > > currently open in /var/lib/php5 and only the "sessions" directory > > contains 100 files, there are far less files below the other directories. > > That's simply because shrinking directories while the file system is > mounted is... tricky. At some point we might try to get this > supported, but until we do, there are two workarounds: ..... > I'm not sure I would call this a bug; it's a long standing proper of > ext2/3/4, the BSD FFS, etc., which is directories can't get shurnk by > the file system. At some point the directory had enough files in it > that it grew to that size, and once having grown to that size, it > won't shirnk on its own. Interesting - I didn't realise that ext4 had this property. I'm so used to XFS where the directory structure grows and shrinks according to it's contents. I learnt something new about ext4 today! > It would be possible to enhance ext4 to be able to shrink directories > on-line, but it would require adding a new file system (to allow > sparse directories), Yeah, XFS directories are sparsely mapped files with internal indexes to maintain constant offset mappings and index free space. It is rather complex... :/ 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
