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To: Thomas David Rivers <ponds!rivers@dg-rtp.dg.com>
cc: dg@root.com, hackers@freebsd.org, joerg@freebsd.org
Subject: Re: daily panics, ffs_valloc: dup alloc - Good news! 
In-reply-to: Your message of "Sun, 09 Feb 1997 13:53:34 EST."
             <199702091853.NAA24339@lakes.water.net> 
Date: Mon, 10 Feb 1997 08:47:39 +0100
Message-ID: <11990.855560859@critter.dk.tfs.com>
From: Poul-Henning Kamp <phk@critter.dk.tfs.com>
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In message <199702091853.NAA24339@lakes.water.net>, Thomas David Rivers writes:
>
>I built a new "newfs", with NTRACKS bumped to 2 and NSECTORS dropped 
>to 2048.
>
>It worked like a champ!  No more panic: ffs_valloc: dup alloc.
>
>I'd say the problem is that the underlying code can't handle one
>track (head).
>
>We should probably go ahead and use this work-around in 2.1.7 and
>2.2.  Perhaps, if we're so inclined, we can determine what a
>better fix would be to keep the 1 track idea.  [It could possibly
>be simply setting fs->fs_cgmask to 0 if the number of tracks is 1; but 
>I'm not sure.]  That investigation could wait until after 2.2 and
>2.1.7.

I've looked at the code, and I cannot see how it could be because
of fs_cgmask being 0xffffffff.

There must be some other explanation.

Do you have the first couple of hundred lines from a dumpfs on the
filesystem (when made with heads=1 ?)

--
Poul-Henning Kamp           | phk@FreeBSD.ORG       FreeBSD Core-team.
http://www.freebsd.org/~phk | phk@login.dknet.dk    Private mailbox.
whois: [PHK]                | phk@tfs.com           TRW Financial Systems, Inc.
Power and ignorance is a disgusting cocktail.