From owner-freebsd-hackers Tue Apr 17 10:45:17 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from earth.backplane.com (earth-nat-cw.backplane.com [208.161.114.67]) by hub.freebsd.org (Postfix) with ESMTP id CC97B37B423 for ; Tue, 17 Apr 2001 10:45:12 -0700 (PDT) (envelope-from dillon@earth.backplane.com) Received: (from dillon@localhost) by earth.backplane.com (8.11.2/8.11.2) id f3HHj2K95255; Tue, 17 Apr 2001 10:45:02 -0700 (PDT) (envelope-from dillon) Date: Tue, 17 Apr 2001 10:45:02 -0700 (PDT) From: Matt Dillon Message-Id: <200104171745.f3HHj2K95255@earth.backplane.com> To: Poul-Henning Kamp Cc: Kirk McKusick , Julian Elischer , Rik van Riel , freebsd-hackers@FreeBSD.ORG, David Xu Subject: Re: vm balance References: <24577.987528856@critter> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :> I don't think NFS relies on vnodes never being freed. : :It does, in some case nfs stashes a vnode pointer and the v_id :value away, and some time later tries to use that pair to try to :refind the vnode again. If you free vnodes, it will still think :the pointer is a vnode and if junk happens to be right it will :think it is still a vnode. QED: Bad things (TM) will happen. : :# cd /sys/nfs :# grep v_id * :nfs_nqlease.c: vpid = vp->v_id; :nfs_nqlease.c: if (vpid == vp->v_id) { :nfs_nqlease.c: if (vpid == vp->v_id && :nfs_vnops.c: vpid = newvp->v_id; :nfs_vnops.c: if (vpid == newvp->v_id) { : :-- :Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 hahahahahahahaha.. Look at the code more closely. v_id is not managed by NFS, it's managed by vfs_cache.c. There's a big XXX comment just before cache_purge() that explains it. Believe me, NFS is the least of your worries here. -Matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message