From owner-freebsd-hackers Sun Jul 5 02:13:55 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id CAA11455 for freebsd-hackers-outgoing; Sun, 5 Jul 1998 02:13:55 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from roma.coe.ufrj.br (jonny@roma.coe.ufrj.br [146.164.53.65]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id CAA11446 for ; Sun, 5 Jul 1998 02:13:51 -0700 (PDT) (envelope-from jonny@jonny.eng.br) Received: (from jonny@localhost) by roma.coe.ufrj.br (8.8.8/8.8.8) id GAA04742; Sun, 5 Jul 1998 06:12:28 -0300 (EST) (envelope-from jonny) From: Joao Carlos Mendes Luis Message-Id: <199807050912.GAA04742@roma.coe.ufrj.br> Subject: Loopback mounts (Was: Variant Link implementation) In-Reply-To: <199807042109.OAA02700@usr02.primenet.com> from Terry Lambert at "Jul 4, 98 09:09:42 pm" To: tlambert@primenet.com (Terry Lambert) Date: Sun, 5 Jul 1998 06:12:28 -0300 (EST) Cc: witr@rwwa.com, hackers@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL40 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG #define quoting(Terry Lambert) // > Note that AMD solves a similiar problem in different way. For // > example, /usr/global/bin gets directed to the correct filesystem // > based on the architecture/os. // // One issue with amd (which is only partially resolvable using the // symlink generation on the mounted fs instead of loopback) is that // loopback mounts via NFS are poison. It is rather easy to hang // every process using the loopback with a nice starvation deadlock // when using it for programs for which the loopback is a swap store. Is mount_null working ? Last time I tried it paniced my machine very often. And mount_umap would be wonderful for some applications, but the effects were even worse. If they work, we could patch amd to use them IFF rhost==thishost. AFAIK, Solaris has been doing this for a long time. Jonny -- Joao Carlos Mendes Luis M.Sc. Student jonny@jonny.eng.br Universidade Federal do Rio de Janeiro "There are two major products that come out of Berkeley: LSD and Unix. We don't believe this to be a coincidence." -- Jeremy S. Anderson To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message