aragonx@xxxxxxxxxx wrote:
I'm wondering at what point ext3 starts having issues with number of files in a directory. For instance, will any of the utilities fail (ls, mv, chown etc) if you have more than x files in a directory? At what point does things really start slowing down? I was told by a coworker that all UNIX varieties have to do an ordered list search when they have to preform any operations on a directory. They also stated that if there is more than 100k files in a directory, these tools would fail. This seems like a low number to me but I was looking for some expert analysis. :) Thanks Will
Your cow-orker is (mostly) wrong! These failures are a shell limitation, and have nothing to do with the filesystem itself.
Ext3 uses hashed directory access, with constant directory access times, if configured properly. I work with some ext3 filesystems that keep over 100K files in a single directory.
Command line utilities fail with "command line is too long" (due to the large number of files), but this is usually easy to work around (man xargs, man find).
I seems to recall that XFS has been tested with a million files in a single directory, but we only use XFS on our SGI IRIX systems.
Things work as expected, but generally things are better with fewer files per directory. Command line length limitation is a major pain for the casual user.
Regards, John
