From owner-freebsd-bugs@FreeBSD.ORG Mon Sep 19 04:30:04 2005 Return-Path: X-Original-To: freebsd-bugs@hub.freebsd.org Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id D3E1A16A41F for ; Mon, 19 Sep 2005 04:30:04 +0000 (GMT) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5315D43D4C for ; Mon, 19 Sep 2005 04:30:04 +0000 (GMT) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.13.3/8.13.3) with ESMTP id j8J4U4EJ066884 for ; Mon, 19 Sep 2005 04:30:04 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.13.3/8.13.1/Submit) id j8J4U4iX066875; Mon, 19 Sep 2005 04:30:04 GMT (envelope-from gnats) Resent-Date: Mon, 19 Sep 2005 04:30:04 GMT Resent-Message-Id: <200509190430.j8J4U4iX066875@freefall.freebsd.org> Resent-From: FreeBSD-gnats-submit@FreeBSD.org (GNATS Filer) Resent-To: freebsd-bugs@FreeBSD.org Resent-Reply-To: FreeBSD-gnats-submit@FreeBSD.org, Erez Zadok Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6A21B16A41F for ; Mon, 19 Sep 2005 04:27:32 +0000 (GMT) (envelope-from nobody@FreeBSD.org) Received: from www.freebsd.org (www.freebsd.org [216.136.204.117]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3B43E43D45 for ; Mon, 19 Sep 2005 04:27:32 +0000 (GMT) (envelope-from nobody@FreeBSD.org) Received: from www.freebsd.org (localhost [127.0.0.1]) by www.freebsd.org (8.13.1/8.13.1) with ESMTP id j8J4RVsT031507 for ; Mon, 19 Sep 2005 04:27:31 GMT (envelope-from nobody@www.freebsd.org) Received: (from nobody@localhost) by www.freebsd.org (8.13.1/8.13.1/Submit) id j8J4RVTg031506; Mon, 19 Sep 2005 04:27:31 GMT (envelope-from nobody) Message-Id: <200509190427.j8J4RVTg031506@www.freebsd.org> Date: Mon, 19 Sep 2005 04:27:31 GMT From: Erez Zadok To: freebsd-gnats-submit@FreeBSD.org X-Send-Pr-Version: www-2.3 Cc: Subject: kern/86319: support a "noac" NFS mount flag to turn off the attribute cache X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Sep 2005 04:30:04 -0000 >Number: 86319 >Category: kern >Synopsis: support a "noac" NFS mount flag to turn off the attribute cache >Confidential: no >Severity: non-critical >Priority: low >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: change-request >Submitter-Id: current-users >Arrival-Date: Mon Sep 19 04:30:03 GMT 2005 >Closed-Date: >Last-Modified: >Originator: Erez Zadok >Release: 5.4 and 6.0 >Organization: Stony Brook University >Environment: All versions of freebsd up to and including 6.0. >Description: To turn off the NFS attribute cache in FreeBSD, one has to set the following four flags to zero in struct nfs_args: nfs_args->acregmin = 0; nfs_args->acregmax = 0; nfs_args->acdirmin = 0; nfs_args->acdirmax = 0; In addition, you have to turn on four flags to tell the kernel that you indeed want it to use your values for the above four flags: nfs_args->flags |= \ (NFSMNT_ACREGMIN|NFSMNT_ACREGMAX|NFSMNT_ACDIRMIN|NFSMNT_ACDIRMAX); This is rather cumbersome and also confusing because some users may be used to what other OSs do: just setting the four fields suffices. For that reason, some OSs like Solaris provide a convenience flag called "noac" that can be set to simply turn off the attribute cache entirely. I would like to ask that FreeBSD support such a convenience flag "noac". In addition, please document this flag and the current behaviour of how one turns off the attribute cache, in the mount_nfs man page. >How-To-Repeat: >Fix: >Release-Note: >Audit-Trail: >Unformatted: