Yes, doing ls on ext3 slows stuff down- still. I've not seen a slowdown that looks like a crash- but.. I have seen a pause.

I keep my sshd running just in case of stuff like that.

Your multilevel system makes more sense. I had the idea that if I had, say, two levels, I would pre write 256 dirs at level 1, then 256 more at each one of those, and then all the possible dirs would be made already. Helping the system along, so I wouldn't have to check that the target absolute location is there or not.

(I'm so glad I asked about this- really impressed by the responses and ideas.)

Hm... may be time to start scripting some .t s .. :-)