From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750808AbVK3Ci0 (ORCPT ); Tue, 29 Nov 2005 21:38:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750816AbVK3Ci0 (ORCPT ); Tue, 29 Nov 2005 21:38:26 -0500 Received: from mail.dvmed.net ([216.237.124.58]:12721 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S1750808AbVK3CiZ (ORCPT ); Tue, 29 Nov 2005 21:38:25 -0500 Message-ID: <438D108A.6020709@pobox.com> Date: Tue, 29 Nov 2005 21:38:02 -0500 From: Jeff Garzik User-Agent: Mozilla Thunderbird 1.0.7-1.1.fc4 (X11/20050929) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Steve Dickson CC: Trond Myklebust , Linux NFS Mailing List , linux-kernel Subject: Re: NFS cache consistancy appears to be broken... References: <200510281607.j9SG7Tll024133@hera.kernel.org> <438D0E80.2020905@RedHat.com> In-Reply-To: <438D0E80.2020905@RedHat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: 0.1 (/) X-Spam-Report: Spam detection software, running on the system "srv2.dvmed.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Steve Dickson wrote: > Hey Trond, > > The attached patch seems to break cache consistence in a big way.... > Doing the following: > 1. On server: > $ mkdir ~/t > $ echo Hello > ~/t/tmp > > 2. On client, wait for a string to appear in this file: > $ until grep -q foo t/tmp ; do echo -n . ; sleep 1 ; done > > 3. On server, create a *new* file with the same name containing that > string: > $ mv ~/t/tmp ~/t/tmp.old; echo foo > ~/t/tmp > > will shows how the client will never (and I mean never ;-) ) see > the updated file. I reverted this patch and everything started > work as expected... so it appears using a jiffy-based cache > verifiers may not be such a good idea.... > > Note: I am using 2.6.15-rc2 kernel. [...] Content analysis details: (0.1 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.1 RCVD_IN_SORBS_DUL RBL: SORBS: sent directly from dynamic IP address [69.134.188.146 listed in dnsbl.sorbs.net] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Steve Dickson wrote: > Hey Trond, > > The attached patch seems to break cache consistence in a big way.... > Doing the following: > 1. On server: > $ mkdir ~/t > $ echo Hello > ~/t/tmp > > 2. On client, wait for a string to appear in this file: > $ until grep -q foo t/tmp ; do echo -n . ; sleep 1 ; done > > 3. On server, create a *new* file with the same name containing that > string: > $ mv ~/t/tmp ~/t/tmp.old; echo foo > ~/t/tmp > > will shows how the client will never (and I mean never ;-) ) see > the updated file. I reverted this patch and everything started > work as expected... so it appears using a jiffy-based cache > verifiers may not be such a good idea.... > > Note: I am using 2.6.15-rc2 kernel. Very interesting. This sounds similar to the problem I reported a week or so ago. The circumstances were too unique to easily reproduce. Jeff