Strange slowdown in one directory

[John Coppens <john jcoppens com>]

Hi all..

Since a couple of weeks, I have a very strange thing with one partition
of my disk mounted as '/data'. GTK+ based programs seem to have
problems accessing this directory after some time.

When the app is recently started, access is fast. After a couple of
hours, it can take up over 30 seconds to 'enter' or 'leave' the directory
with the fileselection menu. I first thought it was a Firefox thing, but
now I'm noticing the same effect in GIMP.

D: contains a lot of files, but few in its root, which is where the delay
occurs. The machine is fast, and RAM is plenty...

Stopping the app, and restarting makes all delay go away. I first thought
about disk unreliability, but I've copied the contents to a new drive.
And its only the root dir in that partition...

Any ideas?
John