ext3 filesystem performance issues

[Bruno Wolff III]

On Wed, Sep 12, 2007 at 16:25:09 -0400,
  Matthew Flaschen <matthew.flaschen at gatech.edu> wrote:
> aragonx at dcsnow.com wrote:
> > 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.
> 
> I'll take that as a challenge.

I have directories with several million files in them. Lookups of a single
file seem to be fast, however I have found mv and cp are unexpectedly slow
and use up lots of memory. So I expect there are some problems with the way
that code was written. I also manually turned on directory indexing. I don't
think that was the default until recently.