> > 
> > mycroft@gnu.ai.mit.edu (Charles M. Hannum) writes:
> > 
> > >Their `fix' will occasionally remove an object that another object is
> > >pointing to, causing stray pointer references.  We were, in fact,
> > >working with Niklas to fix this, but he apparently decided it wasn't
> > >important enough to get it right, and punted.
> > 
> > If I've followed this correctly, the OpenBSD fix:
> > 
> > 	i) collapses shadow-copy object chains by copying
> > 	   swap pages from one object to another, (i.e., involving paging
> > 	   and copying), and
> 
> Well, there are several cases, the most common is actually just renaming
> pages which is cheap.  There is however the "expensive" case which occurs
> very seldom, and that requires pagein alright.  Actually BSD/OS skips this
> case, apparently just the "cheap" collapsing operation suffices for them.

Now I can see why the BSD/OS fix doesn't work in my BSD/OS machines at all.
That case probably is not as rare as you think.

-- 
Zdenek Salvet                                              salvet@ics.muni.cz 
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           If God had meant for us to be in the Army,
         we would have been born with green, baggy skin.