From owner-freebsd-fs@FreeBSD.ORG Fri Feb 6 17:27:21 2009 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5B9AD1065670 for ; Fri, 6 Feb 2009 17:27:21 +0000 (UTC) (envelope-from admin@kedvenc.hu) Received: from site.hu (site.hu [212.92.23.185]) by mx1.freebsd.org (Postfix) with ESMTP id 159E78FC1E for ; Fri, 6 Feb 2009 17:27:20 +0000 (UTC) (envelope-from admin@kedvenc.hu) Received: from www-data by site.hu with local (Exim 4.63 #1 (Debian)) id 1LVUU2-0003Kn-Fq; Fri, 06 Feb 2009 18:27:18 +0100 Received: from 92-249-229-208.pool.digikabel.hu (92-249-229-208.pool.digikabel.hu [92.249.229.208]) by www.site.hu (Horde MIME library) with HTTP; Fri, 06 Feb 2009 18:27:18 +0100 Message-ID: <20090206182718.dhsvxzt7r4sswos4@www.site.hu> X-Priority: 3 (Normal) Date: Fri, 06 Feb 2009 18:27:18 +0100 From: Joe7 To: Rick Macklem References: <20090205212511.jrmipmazeo4o0c8w@www.site.hu> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-2; DelSp="Yes"; format="flowed" Content-Disposition: inline Content-Transfer-Encoding: quoted-printable User-Agent: Internet Messaging Program (IMP) H3 (4.1.4) Cc: freebsd-fs@freebsd.org Subject: Re: nfs delay causing broken files X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Feb 2009 17:27:21 -0000 Hi, Thank you for reply, but: I'm afraid sync mount is not an option: mount_nfs: -o sync: option not supported Tried acregmax=3D0 already, and that made no difference unfortunately. Application level O_DIRECT is not an option for us, so I'm wondering =20 what can be done at mount level? thanks, Joe Id=E9zet (Rick Macklem ): > > > On Fri, 6 Feb 2009, Rick Macklem wrote: > > [stuff snipped] >> >> If the recent writes need to be visible on other clients (and not just th= e >> NFS server), you will also have to bypass the client side caching for >> readers. This can be done by setting nfs_directio_enable to non-zero >> using sysctl and opening the files with O_DIRECT. (I think setting >> acregmax=3D0 as a mount option should achieve the same result, if you can= 't >> add O_DIRECT to the apps.) Again, a big performance hit, but... >> > I know it's weird to reply to my own post, but I realized I should clarify > that setting acregmax=3D0 will only achieve this approximately, based on > the clock resolution used for the file's modify time. Setting acregmax=3D0 > should disable client side attribute caching, such that the client always > does a Getattr against the server. Then, if the mtime attribute for the > file has changed since the client cached data, it will be purged. As such, > this only works when the mtime has changed and that will be based upon > clock resolution (and if the mtime got saved on the server's disk, for the > case where the server has crashed/rebooted). > > Have a good weekend, rick