Subject: Re: Am I under attack or what?
To: None <current-users@NetBSD.ORG>
From: Geoff Wing <>
List: current-users
Date: 01/19/1998 17:15:55
Frank van der Linden <> typed:
:On Mon, Jan 19, 1998 at 11:50:01AM -0500, D'Arcy J.M. Cain wrote:
:> I'm still having these hangs.  I have another clue.  Out of 3 machines
:> running NetBSD 1.3, this is the only one using union mounts.  Is it
:> possible that the union mount code is getting messed up and jamming
:> the system?  Thinking about it, we recently moved our web page to
:> a directory involved in union mounting.  Although the union mounts
:> were there all along (and were accessed) this is the first time that
:> it would have been hit steadily.  I did test the new pages after
:> the switch without problems but perhaps there is something else I
:> am missing that has to happen at the same time.
:I would not use union mounts for a "production" filesystem.. it could
:be the source of your problems. Maybe you should try disabling it.

I'd give it a 99% likelihood of being the problem.  Union mount code is
not stable at all.  There are dozens of things you can do that will crash
your system if you're using them.  Actually, I use union mounts a lot, eg.
mounting my /usr/obj dir on top of my /usr/src dir when compiling, but I 
make sure I only have one shell cd'd in there, and I only start one 
task set.  Doing simple things like make in two different dirs will crash
you quickly.
Geoff Wing []                         Phone    : +61-3-9818 2977
 Technical Manager: PrimeNet Computer Consultants  Facsimile: +61-3-9818 5155
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