From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FC4FC433E0 for ; Mon, 25 May 2020 06:08:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 787172071A for ; Mon, 25 May 2020 06:08:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="q1Zop2oN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727894AbgEYGIQ (ORCPT ); Mon, 25 May 2020 02:08:16 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:33926 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726515AbgEYGIP (ORCPT ); Mon, 25 May 2020 02:08:15 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04P621EH062217; Mon, 25 May 2020 06:08:13 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : content-transfer-encoding : in-reply-to; s=corp-2020-01-29; bh=BAKZis/ST/EocxNsZQqpJJMMmheS0IxSkj0K1u/zdqk=; b=q1Zop2oN3mFPgegVoopJ9GxyiQF8/VJOhPLn+/wWI5UQ3JzlEpkYBhVuNNfqbldz/RIi jc5Pg8XzaMUNM3QdhIPSuEEzQIynzt+gmhMSTP3yyoVsR3Xc8d9WCc6zaS6s9c2+X6ze VYfgS1nh/C6IbMz/ZXwVBHyeTgiYpF0TapxA4Go+jylwuq3Oh0UwKXTU6lJQMTkjQcRl xQTuQYobjNmf8m7zJbWxHRGGeboFYdsESf2zS3QJq0Ar9weZebSrZh5JwAFZlFQHfteO mQ9DakIcCvMGU7BiZbdKiOOuhhK+QvMWUsE+WTBeL4Z+pLPqEPtsEsExvqgwskAtu4CM Kg== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 316uskm514-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 25 May 2020 06:08:13 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04P63RsR141347; Mon, 25 May 2020 06:08:12 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3020.oracle.com with ESMTP id 317dkq1d9p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 25 May 2020 06:08:12 +0000 Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 04P686YP012375; Mon, 25 May 2020 06:08:11 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sun, 24 May 2020 23:08:06 -0700 Date: Sun, 24 May 2020 23:08:04 -0700 From: "Darrick J. Wong" To: Dave Chinner Cc: Emmanuel Florac , linux-xfs@vger.kernel.org Subject: Re: [XFS SUMMIT] Deprecating V4 on-disk format Message-ID: <20200525060804.GC252930@magnolia> References: <20200513023618.GA2040@dread.disaster.area> <20200519062338.GH17627@magnolia> <20200520011430.GS2040@dread.disaster.area> <20200520151510.11837539@harpe.intellique.com> <20200525032354.GV2040@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200525032354.GV2040@dread.disaster.area> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9631 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 malwarescore=0 bulkscore=0 spamscore=0 suspectscore=1 mlxscore=0 adultscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005250050 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9631 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 lowpriorityscore=0 suspectscore=1 spamscore=0 priorityscore=1501 clxscore=1011 impostorscore=0 bulkscore=0 mlxlogscore=999 phishscore=0 cotscore=-2147483648 adultscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005250050 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Mon, May 25, 2020 at 01:23:54PM +1000, Dave Chinner wrote: > On Wed, May 20, 2020 at 03:15:10PM +0200, Emmanuel Florac wrote: > > Le Wed, 20 May 2020 11:14:30 +1000 > > Dave Chinner écrivait: > > > > > Well, there's a difference between what a distro that heavily > > > patches the upstream kernel is willing to support and what upstream > > > supports. And, realistically, v4 is going to be around for at least > > > one more major distro release, which means the distro support time > > > window is still going to be in the order of 15 years. > > > > IIRC, RedHat/CentOS v.7.x shipped with a v5-capable mkfs.xfs, but > > defaulted to v4. That means that unless you were extremely cautious > > (like I am :) 99% of RH/COs v7 will be running v4 volumes for the > > coming years. How many years, would you ask? > > Largely irrelevant to the question at hand, as support is dependent > on the distro lifecycle here. Essentially whatever is in RHEL7 is > supported by RH until the end of it's life. > > In RHEL8, we default to v5 filesystems, but fully support v4. That > will be the case for the rest of it's life. Unless the user > specifically asks for it, no new v4 filesystems are being created on > current RHEL releases. > > If we were to deprecate v4 now, then it will be marked as deprecated > in the next major RHEL release. That means it's still fully > supported in that release for it's entire life, but it will be > removed in the next major release after that. So we are still > talking about at least 15+ years of enterprise distro support for > the format, even if upstream drops it sooner... We probably ought to do it sooner than later though, particularly if we think/care about 5.9 turning into an LTS. > > As for the lifecycle of a filesystem, I just ended support on a 40 TB > > archival server I set up back in 2007. I still have a number of > > supported systems from the years 2008-2010, and about a hundred from > > 2010-2013. That's how reliable XFS is, unfortunately :) > > Yup, 10-15 years is pretty much the expected max life of storage > systems before the hardware really needs to be retired. We made v5 > the default 5 years ago, so give it another 10 years (the sort of > timeframe we are talking about here) and just about > everything will be running v5 and that's when v4 can likely be > dropped. > > The other thing to consider is that we need to drop v4 before we get > to y2038 support issues as the format will never support dates > beyond that. Essentially, we need to have the deprecation discussion > and take action in the near future so that people have stopped using > it before y2038 comes along and v4 filesystems break everything. > > Not enough people think long term when it comes to computers - it > should be more obvious now why I brought this up for discussion... Ok then, who would like to help me get the y2038 timestamp patches reviewed for ~5.9? :D (Anyone; not necessarily Dave) --D > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com