Jon Craig wrote: > 2009/8/31 Christian Völker <chrisc...@knebb.de>: >> Yohoo! >>> With backuppc the issue is not so much fragmentation within a file as >>> the distance between the directory entry, the inode, and the file >>> content. When creating a new file, filesystems generally attempt to >>> allocate these close to each other, but when you link an existing file >>> into a new directory, that obviously can't be done so you end up with a >>> lot of long seeks when you try to traverse directories picking up the >>> inode info. > > I believe you are mistaken in this. Your confusing directory entries > with inode entries.
No, I'm saying that the filesystem has a choice about what inode and free space to use when the first entry is created. And a sensible filesystem will try to cluster them or at least keep the inodes allocated for files created in the same directory close together. > When you hard link a file from one directory to > another you have two directory entries pointing to the same inode. And the new directory entry may be all the way across the disk from the existing inode - and far from any other inode in this directory. > You can do a simple test by touching a file and then make a hard link > to a new file and list with "ls -li". You will see that both files > share the same inode number. And, assuming you have enough disk activity to keep the cache out of date, that 'ls -l' will have to move the disk head to the directory location and then the inode to get the data - if you list many files in the same directory that were links to existing files, the head may have to seek all over the place to get the inoded data. -- Les Mikesell lesmikes...@gmail.com ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/