From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751366AbWCaPYF (ORCPT ); Fri, 31 Mar 2006 10:24:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751386AbWCaPYE (ORCPT ); Fri, 31 Mar 2006 10:24:04 -0500 Received: from unthought.net ([212.97.129.88]:33296 "EHLO unthought.net") by vger.kernel.org with ESMTP id S1751387AbWCaPYC (ORCPT ); Fri, 31 Mar 2006 10:24:02 -0500 Date: Fri, 31 Mar 2006 17:24:01 +0200 From: Jakob Oestergaard To: "Bill Rugolsky Jr." , Trond Myklebust , linux-kernel@vger.kernel.org Subject: Re: NFS client (10x) performance regression 2.6.14.7 -> 2.6.15 Message-ID: <20060331152401.GM9811@unthought.net> Mail-Followup-To: Jakob Oestergaard , "Bill Rugolsky Jr." , Trond Myklebust , linux-kernel@vger.kernel.org References: <20060331124518.GH9811@unthought.net> <1143810392.8096.11.camel@lade.trondhjem.org> <20060331132131.GI9811@unthought.net> <1143812658.8096.18.camel@lade.trondhjem.org> <20060331140816.GJ9811@unthought.net> <1143814889.8096.22.camel@lade.trondhjem.org> <20060331143500.GK9811@unthought.net> <20060331144951.GA9207@ti64.telemetry-investments.com> <20060331145726.GL9811@unthought.net> <20060331150453.GB9207@ti64.telemetry-investments.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060331150453.GB9207@ti64.telemetry-investments.com> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 31, 2006 at 10:04:53AM -0500, Bill Rugolsky Jr. wrote: > On Fri, Mar 31, 2006 at 04:57:26PM +0200, Jakob Oestergaard wrote: > > True. But it is my impression that this is a problem isolated on the > > client side (am I wrong?) > > That seems to be the case. Hmm... > > > Do you mean NFS exporting a local filesystem, NFS mounting it again on > > the local host? Or do you mean something with loopback mounts? > > The former; just export a local directory to 127.0.0.1 in /etc/exports, > then mount it on /mnt. With a local export/mount I see very few reads running the test :/ Could this be a timing issue? That pages in the cache are invalidated after maybe less than 100 microseconds which is roughly the round-trip time on the gigabit network connecting my server and client? /proc/self/mountstats on the two filesystems look identical to me: device sparrow:/exported/joe mounted on /u/joe with fstype nfs statvers=1.0 opts: rw,vers=3,rsize=32768,wsize=32768,acregmin=3,acregmax=60, acdirmin=30,acdirmax=60,hard,intr,proto=udp,timeo=7,retrans=3 device localhost:/home/test mounted on /mnt with fstype nfs statvers=1.0 opts: rw,vers=3,rsize=32768,wsize=32768,acregmin=3,acregmax=60, acdirmin=30,acdirmax=60,hard,intr,proto=udp,timeo=7,retrans=3 -- / jakob