From: Aaron Straus Subject: Re: [NFS] blocks of zeros (NULLs) in NFS files in kernels >= 2.6.20 Date: Thu, 11 Sep 2008 10:19:08 -0700 Message-ID: <20080911171908.GE12037@merfinllc.com> References: <20080905191939.GG22796@merfinllc.com> <0A24B45A-9761-4310-B1DB-B4738964E862@oracle.com> <20080908190212.GF28123@merfinllc.com> <76bd70e30809081415h6b55a8dfl8171634c576ac946@mail.gmail.com> <20080909194644.GI5290@merfinllc.com> <8BFB4AE0-3EF1-41FA-A13B-27E380A79950@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Neil Brown , Linux NFS Mailing List , Trond Myklebust , LKML Kernel To: Chuck Lever Return-path: Received: from quackingmoose.com ([63.73.180.143]:36396 "EHLO penguin.merfinllc.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752230AbYIKRTJ (ORCPT ); Thu, 11 Sep 2008 13:19:09 -0400 In-Reply-To: <8BFB4AE0-3EF1-41FA-A13B-27E380A79950@oracle.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Hi, On Sep 11 12:55 PM, Chuck Lever wrote: > A more thorough review of the NFS write and flush logic that exists in > 2.6.27 is needed if we choose to recognize this issue as a real > problem. Yep. Sorry. I didn't mean we should revert the hunk. I was just trying to help identify the cause of the new behavior. I think this is a real problem albeit not a "serious" one. Network file-systems usually try to avoid readers seeing blocks of zeros in files, especially in this simple writer/reader case. It wouldn't be bad if the file is written out of order occasionally, but we see this constantly now. We cannot write/read log files to NFS mounts reliably any more. That seems like a valid use case which no longer works? Anyway, thanks for your time! =a= -- =================== Aaron Straus aaron-bYFJunmd+ZV8UrSeD/g0lQ@public.gmane.org