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From: Terry Lambert <terry@lambert.org>
Message-Id: <199509131752.KAA07769@phaeton.artisoft.com>
Subject: Re: Is nullfs broken in -current?
To: roberto@keltia.freenix.fr (Ollivier Robert)
Date: Wed, 13 Sep 1995 10:52:16 -0700 (MST)
Cc: wollman@lcs.mit.edu, terry@lambert.org, current@freefall.freebsd.org
In-Reply-To: <199509122200.AAA19788@keltia.Freenix.FR> from "Ollivier Robert" at Sep 13, 95 00:00:24 am
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> It seems that Garrett A. Wollman said:
> > # mount -t null -o union /dsk2/src1 /usr/src
> > # mount -t null -o union /dsk3/src2 /usr/src
> > # cd /usr/src
> > # make world

This one is a unionfs, not a nullfs.

> This one is a winner too:
> 
> # mount -t null /src/src /usr/src
> # cvs update -d -P

You are replacing the /usr/src vnode (potentially on cdrom) with the
/src/src vnode from a writeable media?

This seems more useful and applicable.

I'll look at it.  I suspect some of the problem is the delay in the
vnode alias should not be occuring for the mount point itself.

Part of this could be a cache issue.  The name cache wants to be moved
to the lookup layer instead of being implemented in each subsidiary
file system.  It doesn't look like the cache is flushed for the top
level vnode, so potentially stale data is being returned.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.