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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 88EA0CA9EAF for ; Thu, 24 Oct 2019 13:23:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57F882084C for ; Thu, 24 Oct 2019 13:23:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="aar+YxQE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2502540AbfJXNXd (ORCPT ); Thu, 24 Oct 2019 09:23:33 -0400 Received: from mail-lf1-f42.google.com ([209.85.167.42]:41820 "EHLO mail-lf1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2502538AbfJXNXc (ORCPT ); Thu, 24 Oct 2019 09:23:32 -0400 Received: by mail-lf1-f42.google.com with SMTP id x4so12843740lfn.8 for ; Thu, 24 Oct 2019 06:23:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:content-transfer-encoding:mime-version:subject:message-id:date :cc:to; bh=zd3gqhuIRD+EIRndf+SmDBrEPsFc0s2TNeeNdYV60II=; b=aar+YxQEfNoO9pb3tVll4bn5ygE/5+C5Wh8HwuNu5aveJNt3iP/NfIgzBzqZIwbjr4 ZoA4l27u4SbMBX76qXbtbQNehnEI3p1pJ1QnJ+fTYC/yJqUFZjpanJR+gvl86yVHvu3k D/0MguX+Hx8PXwaZQmKvYMhSKXU1n2aJ70nC/vgAMJR+rQaONBJ0PL0tn34hjMSv6Hjx xK5cYwlqXyvI2x1XqjT4bVqGKk47es1sAmSBqFMB2knMCOSU4MAciF5BQFN7J8NFXepD sSv1m+TgpHj6QUy8nR1fQSsQIzhHRy4YjvibrNg7gA633XSWJSkDfM6eBQTQQC9f4Zyo gONw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:content-transfer-encoding:mime-version :subject:message-id:date:cc:to; bh=zd3gqhuIRD+EIRndf+SmDBrEPsFc0s2TNeeNdYV60II=; b=CaUol+Kr2oN7p9mYENPHAfmcVlV0reEUpppC2POyu29kNdphmrJsmF+pj/UZ1FYwJD iWfXva5+71+Mn2xmxGb6zU0fr1vhxlatQ8f1sndchip9zUZ36yORdq+Bzp9TiwaTi8NW dpPX1mVVdnrSwpg2fOGrIjtQ75xmY+2rdsoesgRdC5sOzkmzx2Hf0LAA3hW6KFb5sJys BGulhJCaCc5RB7VmcWuzV3v8mpfoTM5roRr2r5dRx9RJUZWbTpl3zDXL8cpltYRM7tWH LDkTb1Z/mya+SiQdk0jxHMOWesAnYryZVflBkfbpWxv4CBa5CZjoLgzSkLEt+/iVm9AU z+tQ== X-Gm-Message-State: APjAAAVfesPUnYInRxpUQNwJEZt/b/nmJZ7mDWTIfiNkkhs1ZCp5VMUx JJXPJ5B9HjG3GahWL/S7p1s32qSc4iv8gg== X-Google-Smtp-Source: APXvYqyPtuiWajQ0MktDddf/rIMKX6bfgZz8jBbXwq2GGVSzrOWWzKVCZZvReIPSigqqJ6IOFwYPxg== X-Received: by 2002:a19:6a08:: with SMTP id u8mr28411705lfu.74.1571923410446; Thu, 24 Oct 2019 06:23:30 -0700 (PDT) Received: from [192.168.43.113] ([95.153.130.220]) by smtp.gmail.com with ESMTPSA id y8sm10174448ljh.21.2019.10.24.06.23.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Oct 2019 06:23:29 -0700 (PDT) From: =?utf-8?B?0JHQu9Cw0LPQvtC00LDRgNC10L3QutC+INCQ0YDRgtGR0Lw=?= Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: 1024TB Ext4 partition Message-Id: <8A6F6DF3-F920-4291-91C2-E4AAF1E63ADE@gmail.com> Date: Thu, 24 Oct 2019 16:23:15 +0300 Cc: Andreas Dilger , "Theodore Y. Ts'o" To: linux-ext4 X-Mailer: Apple Mail (2.3273) Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Hello, Lustre FS successfully uses LDISKFS(ext4) partitions with size near = 512TB. This 512TB is current "verified limit". This means that we do not expect = any troubles in production with such large partitions. Our new challenge now is 1024TB because hardware allows to assemble such = partition. The question is: do you know any possible issues with EXT4 (and = e2fsprogs) for such large partitions? I know about this possible problems: 1. E2fsck is too slow. But parallel e2fsck project is being developed by = Li Xi 2. Block groups reading takes a lot of time. We have fixes for special = cases like e2label.=20 Bigalloc also allows to decrease metadata size, but sometimes = meta_bg is preferable. 3. Aged fs and allocator that process all groups to find good group. = There is solution, but with some issues. 4. 32 bit inode counter. Not a problem for Lustre FS users, that prefer = use DNE for inode scaling, but probably somebody wants to store a lot inodes on the same = partition. Project was not finished. Looks nobody require it now. =20 Could you please, point me to other possible problems? Thanks. Artem Blagodarenko.