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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 4AA3EC43441 for ; Fri, 9 Nov 2018 23:05:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D29992081C for ; Fri, 9 Nov 2018 23:05:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D29992081C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=techsingularity.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-btrfs-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728057AbeKJIsS (ORCPT ); Sat, 10 Nov 2018 03:48:18 -0500 Received: from outbound-smtp02.blacknight.com ([81.17.249.8]:49712 "EHLO outbound-smtp02.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727746AbeKJIsS (ORCPT ); Sat, 10 Nov 2018 03:48:18 -0500 X-Greylist: delayed 531 seconds by postgrey-1.27 at vger.kernel.org; Sat, 10 Nov 2018 03:48:17 EST Received: from mail.blacknight.com (pemlinmail03.blacknight.ie [81.17.254.16]) by outbound-smtp02.blacknight.com (Postfix) with ESMTPS id B0DDF98979 for ; Fri, 9 Nov 2018 22:56:43 +0000 (UTC) Received: (qmail 16863 invoked from network); 9 Nov 2018 22:56:43 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[37.228.229.69]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 9 Nov 2018 22:56:43 -0000 Date: Fri, 9 Nov 2018 22:56:42 +0000 From: Mel Gorman To: Josef Bacik Cc: Filipe Manana , David Sterba , linux-btrfs@vger.kernel.org Subject: Re: [Regression bisected] btrfs: always wait on ordered extents at fsync time Message-ID: <20181109225642.GG23260@techsingularity.net> References: <20181109215148.GF23260@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20181109215148.GF23260@techsingularity.net> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Nov 09, 2018 at 09:51:48PM +0000, Mel Gorman wrote: > Unfortunately, as > I'm about to travel, I didn't attempt a revert and a test comparing 4.18, > 4.19 and 4.20-rc1 is a few hours away so this could potentially be fixed > already but I didn't spot any obvious Fixes commit. > Still here a few hours later but the regression still appears to exist in mainline and the comparison report is below. While there are slightly differences, the regressions are well outside multiples of the stddev and co-efficient of variance so I'm fairly sure it's real. The one positive thing is that the actual standard deviation is lower so the results are more stable but that is a thin silver lining. reaim 4.18.0 4.19.0 4.20.0-rc1 vanilla vanilla vanilla Min new_dbase-1 703.07 ( 0.00%) 752.74 ( 7.06%) 739.23 ( 5.14%) Min new_dbase-5 6293.28 ( 0.00%) 4158.82 ( -33.92%) 4164.42 ( -33.83%) Min new_dbase-9 16803.63 ( 0.00%) 10948.82 ( -34.84%) 10927.31 ( -34.97%) Min new_dbase-13 25343.85 ( 0.00%) 18640.37 ( -26.45%) 18094.59 ( -28.60%) Min new_dbase-17 38203.64 ( 0.00%) 27430.81 ( -28.20%) 27793.65 ( -27.25%) Min new_dbase-21 45697.18 ( 0.00%) 34700.53 ( -24.06%) 35170.73 ( -23.04%) Min new_dbase-25 54593.64 ( 0.00%) 44269.34 ( -18.91%) 44142.86 ( -19.14%) Min new_dbase-29 60752.54 ( 0.00%) 51797.69 ( -14.74%) 50484.51 ( -16.90%) Min new_dbase-33 59631.58 ( 0.00%) 57610.17 ( -3.39%) 57286.52 ( -3.93%) Hmean new_dbase-1 787.46 ( 0.00%) 821.81 ( 4.36%) 866.52 ( 10.04%) Hmean new_dbase-5 6437.50 ( 0.00%) 4269.14 * -33.68%* 4314.44 * -32.98%* Hmean new_dbase-9 17305.54 ( 0.00%) 11101.80 * -35.85%* 11075.27 * -36.00%* Hmean new_dbase-13 27570.35 ( 0.00%) 19065.02 * -30.85%* 18885.75 * -31.50%* Hmean new_dbase-17 39377.81 ( 0.00%) 27926.64 * -29.08%* 28181.33 * -28.43%* Hmean new_dbase-21 47434.21 ( 0.00%) 36785.71 * -22.45%* 36150.42 * -23.79%* Hmean new_dbase-25 56593.41 ( 0.00%) 45387.78 * -19.80%* 44808.59 * -20.82%* Hmean new_dbase-29 61503.09 ( 0.00%) 52250.73 * -15.04%* 51176.47 * -16.79%* Hmean new_dbase-33 66343.53 ( 0.00%) 58235.29 * -12.22%* 58637.15 * -11.62%* Stddev new_dbase-1 125.91 ( 0.00%) 57.02 ( 54.71%) 88.32 ( 29.86%) Stddev new_dbase-5 174.01 ( 0.00%) 130.71 ( 24.88%) 107.34 ( 38.32%) Stddev new_dbase-9 537.99 ( 0.00%) 114.10 ( 78.79%) 154.87 ( 71.21%) Stddev new_dbase-13 1502.62 ( 0.00%) 352.32 ( 76.55%) 503.48 ( 66.49%) Stddev new_dbase-17 935.76 ( 0.00%) 322.83 ( 65.50%) 279.50 ( 70.13%) Stddev new_dbase-21 1389.92 ( 0.00%) 1425.14 ( -2.53%) 805.66 ( 42.04%) Stddev new_dbase-25 1672.09 ( 0.00%) 875.75 ( 47.63%) 529.71 ( 68.32%) Stddev new_dbase-29 678.85 ( 0.00%) 340.66 ( 49.82%) 852.63 ( -25.60%) Stddev new_dbase-33 3958.22 ( 0.00%) 632.39 ( 84.02%) 845.17 ( 78.65%) CoeffVar new_dbase-1 15.72 ( 0.00%) 6.91 ( 56.03%) 10.10 ( 35.73%) CoeffVar new_dbase-5 2.70 ( 0.00%) 3.06 ( -13.25%) 2.49 ( 7.96%) CoeffVar new_dbase-9 3.11 ( 0.00%) 1.03 ( 66.92%) 1.40 ( 54.99%) CoeffVar new_dbase-13 5.44 ( 0.00%) 1.85 ( 66.02%) 2.66 ( 50.99%) CoeffVar new_dbase-17 2.38 ( 0.00%) 1.16 ( 51.34%) 0.99 ( 58.25%) CoeffVar new_dbase-21 2.93 ( 0.00%) 3.87 ( -32.14%) 2.23 ( 23.92%) CoeffVar new_dbase-25 2.95 ( 0.00%) 1.93 ( 34.67%) 1.18 ( 59.97%) CoeffVar new_dbase-29 1.10 ( 0.00%) 0.65 ( 40.93%) 1.67 ( -50.92%) CoeffVar new_dbase-33 5.95 ( 0.00%) 1.09 ( 81.74%) 1.44 ( 75.77%) Max new_dbase-1 1019.80 ( 0.00%) 900.87 ( -11.66%) 973.23 ( -4.57%) Max new_dbase-5 6717.39 ( 0.00%) 4446.04 ( -33.81%) 4414.29 ( -34.29%) Max new_dbase-9 18058.44 ( 0.00%) 11259.11 ( -37.65%) 11304.88 ( -37.40%) Max new_dbase-13 28795.70 ( 0.00%) 19547.45 ( -32.12%) 19452.78 ( -32.45%) Max new_dbase-17 40407.69 ( 0.00%) 28241.94 ( -30.11%) 28548.91 ( -29.35%) Max new_dbase-21 48973.58 ( 0.00%) 38283.19 ( -21.83%) 37080.00 ( -24.29%) Max new_dbase-25 59195.40 ( 0.00%) 46676.74 ( -21.15%) 45307.92 ( -23.46%) Max new_dbase-29 62445.99 ( 0.00%) 52711.76 ( -15.59%) 52557.18 ( -15.84%) Max new_dbase-33 69132.20 ( 0.00%) 59284.88 ( -14.24%) 59457.73 ( -13.99%) -- Mel Gorman SUSE Labs