From owner-freebsd-current Mon Oct 25 10:26: 8 1999 Delivered-To: freebsd-current@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by hub.freebsd.org (Postfix) with ESMTP id 249AE14F59 for ; Mon, 25 Oct 1999 10:26:06 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id KAA07728; Mon, 25 Oct 1999 10:26:04 -0700 (PDT) (envelope-from dillon) Date: Mon, 25 Oct 1999 10:26:04 -0700 (PDT) From: Matthew Dillon Message-Id: <199910251726.KAA07728@apollo.backplane.com> To: David Wolfskill Cc: freebsd-current@FreeBSD.ORG Subject: Re: freefall hangs w/ nfs References: <199910251436.HAA20848@pau-amma.whistle.com> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG : :>Date: Sun, 24 Oct 1999 00:42:12 -0700 (PDT) :>From: Matthew Dillon : :> It looks on the face of it that AMD is hanging. Perhaps this is :> preventing the system from clearing out buffers and causing lockups :> on other mounts. AMD could also be causing a deadlock to occur in the :> buffer cache (for the same reason loopback mounts can cause deadlocks). : :> The next time this happens, if the person rebooting freefall can get :> a kernel dump (and have a corresponding debug kernel) I may be able to :> track it down for sure. Fixing it is another problem, though. Loopback :> deadlocks are a big problem under 3.x. : :In an environment where there is use of amd and NFS, there is no need :for loopback NFS mounts. Actually, what I meant was that AMD itself is equivalent to a loopback mount, whether or not you make loopback mounts through it. In looking at freefall a bit more, I don't quite understand why amd is being used at all. I would simply create a /net/freefall/{c,d,g,x} and mount /c, /d, /g, and /x there locally. Then on hub and bento the same paths would simply be NFS mounts. This would allow everyone's home directories to be hard coded on all machines to /net/freefall/blahblahblah. This is essentially what I did when we had shell1 and shell2 during the early days of BEST. -Matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message