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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 054A1C10F25 for ; Tue, 10 Mar 2020 02:18:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C91DC2146E for ; Tue, 10 Mar 2020 02:18:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="k6Kqhn+E" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726512AbgCJCSq (ORCPT ); Mon, 9 Mar 2020 22:18:46 -0400 Received: from mout.gmx.net ([212.227.15.15]:36219 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726156AbgCJCSp (ORCPT ); Mon, 9 Mar 2020 22:18:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1583806718; bh=tlZDJfP/4Uep1REJOHjJ8t3rWJkZuals4yw6EusfX10=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=k6Kqhn+EIbhs/+Z8PTTvRAKCuTKhddnCVCF3Cla2PAh4lwRmAPkWLopN+kyqQMQ+3 3EDv1RZIYEtJOSZhbeN3Vbs7QgjdbwQuAEfpZswIE8gUQzMdQysxo0ZOEs2hzhdzpJ V+3CiQAlQB3wT61SsVu8SQS7a3dOFLfGdVEDmAAM= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.com (mrgmx004 [212.227.17.184]) with ESMTPSA (Nemesis) id 1Mk0JW-1jduKb2wS8-00kNUF; Tue, 10 Mar 2020 03:18:38 +0100 Subject: Re: ENOSPC in btrfs_drop_snapshot with 5.4.21 To: Martin Raiber , "linux-btrfs@vger.kernel.org" , Josef Bacik , Nikolay Borisov References: <01020170c1c26e04-031eb2cc-f2da-4ba3-b259-986730cfae7a-000000@eu-west-1.amazonses.com> <01020170c22e02f3-0fac99b3-1cb9-4d17-88e8-4d6bab41d934-000000@eu-west-1.amazonses.com> From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: Date: Tue, 10 Mar 2020 10:18:33 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <01020170c22e02f3-0fac99b3-1cb9-4d17-88e8-4d6bab41d934-000000@eu-west-1.amazonses.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:gjf+5K9LEJB7/LMDkRpVkF06mhn+tWRcUvvFLWmd19YFszs+jdb +C+KCtvGIGEo3MkGUn8zEe6C4s/kIJyL32U2gW+cChuOBD6+ZesJq4yUyON9SIJD8ah9hgF NXxStFbT1+qLv2ENK3KE044c0DAAZt9XNBZzqxbGnenUPiSCErrny2YJz3o+AOorCdwnScD lz7UrlYd5kq5ee9ZHJDsg== X-UI-Out-Filterresults: notjunk:1;V03:K0:MO8pA2p30II=:aE2qPaEgt2w7INuNNLBl58 hZNbbLz341XqSISlzSjnhoRl7ChN0/1EjmE2ZJTmkI5vHg4Zz69qGljV2zhF2LPfoYmUc0+n2 AblacCklVor1IKvwF1Xk65r9PW2FPdbxSBO06wPMWhcQFpSHL/IiupkvZpNc8db0hW2McXhr/ 5n4hYp+JCj+ycL/smE3+072g9H44qf+Tkry5GTwX1o/BTV144gjRUyJpZy/YqWPRnw5+2IM8Y 43mQWFgwMpil/lseSYuiNJTa8jYxlO3QeMtTdPJU3cv75oq8KTPG+DLj5s235RzIWwUJJHr+P ey7nf3eFePD1K1ZUZnuDxPu4QsjsL4d5XReH2mU8a9EJMu8ooukng7AY6A0N0xo7IHSbGP6Rz v/tpNKxHNCvyryqQvEOepmBpurpfhjqNOc0YRkvCzYs1ya5TWqWiviCH0WkxQ0wufP8LQbkpc f/p4KQF56SOUXuyYozxD7O4rCcQsE8Xv74G0qg2irWHj4U8a/HYJ2csCzicetdRzgeq38yxdE nyR7/ywHTLxuxDqy5zouX2ddVqXL9VdXw6n9IfIZgIsjeSlPWiyuF+79vYhh8R0tFyP9CP1ym /pcLJXJF1icuAPJmy7JGBtg5R6G8q4fYPc4mK5ebMg4TawsSwHa9LDkjgBqEgII7iR5gWfTl/ B/T76ucn3Up9jqCyQ/E4Kn936OTxob+xsJogdhR1q+AflgOqugtomxfYSJ/zsWqj1rbh9JKEa Obo36WbGdPG4spTMGKfwp/6MEy+/rueoOFSkPoDRLBbofuNZs7YVlnH6Iv3kOLbTUuEXqcWO3 l/cnec8SlAhyAOrX76TH8sKbUFWEN/z0gOsI8hk/v3yQD/lE4Gg21MGA/3ZtDGYa+7GrHGtu7 aVQof22ZZA0yauTi7/QBMLlyTPkIOpqnlMShq3XV2hCxajA5/Ez34kZhuiZNiGWlTIB5ZQmrr /fIAVLaB/VID3qmxW8OjsVjlhJowEzbdJkHXqAKEDjGOOd7uxUsBNfD0XH+4hVa5NmDKKskHU Pv72OpQmnja10WFLXg9xNySSB+wUcFBaCOWwWn5RFdaF8VLFplrohbwpmqlN/Y7AWbSX6wNZB jcyAMF0e2sFY7Fx49fozL5x+xq8EBkGj+NIrVENGcPPsfeWsBRKS7DNnbq5iZBNZ035MrFEPA t3I8dWB2OdsFhvH82UO8VX8/FHoSdHU7VdAVxytng+kFus3FruxQ8McUyAKzmbg9eMxzp9M2D TDJnkm5RZJeQ8p6d5 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2020/3/10 =E4=B8=8A=E5=8D=8810:02, Martin Raiber wrote: > On 10.03.2020 02:41 Qu Wenruo wrote: >> >> On 2020/3/10 =E4=B8=8A=E5=8D=888:05, Martin Raiber wrote: >>> Hi, >>> >>> I get a enospc to remount-ro with 5.4.21. Details: >> Sorry, the attached dmesg doesn't contain the transaction abort message= . >> >> It only has the flooded ENOSPC from enospc_debug option. > > This isn't it? > > [76641.627535] BTRFS: error (device dm-0) in btrfs_drop_snapshot:5419: > errno=3D-28 No space left > [76641.627549] BTRFS info (device dm-0): forced readonly > [...] Sorry, forgot it's not calling btrfs_abort_transaction() but btrfs_handle_fs_error(), thus no backtrace. Then it's too many pinned bytes from dropped snapshot caused the problem. And since we're holding one transaction without ending it, it prevents ticketed space system to flush and free space. It looks like the check in should_end_transaction() is not good enough. Maybe Josef and Nikolay could have some better ideas on this? Thanks, Qu > >> >> Thanks, >> Qu >>> Linux 5.4.21 #1 SMP Fri Feb 21 03:20:26 CET 2020 x86_64 GNU/Linux >>> >>> btrfs fi usage /media/btrfs (after remount-ro) >>> Overall: >>> =C2=A0=C2=A0=C2=A0 Device size:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 511.99GiB >>> =C2=A0=C2=A0=C2=A0 Device allocated:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 511.99GiB >>> =C2=A0=C2=A0=C2=A0 Device unallocated:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0.00B >>> =C2=A0=C2=A0=C2=A0 Device missing:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0.00B >>> =C2=A0=C2=A0=C2=A0 Used:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0 443.68GiB >>> =C2=A0=C2=A0=C2=A0 Free (estimated):=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 54.94GiB=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0 (min: 54.94GiB) >>> =C2=A0=C2=A0=C2=A0 Data ratio:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0 1.00 >>> =C2=A0=C2=A0=C2=A0 Metadata ratio:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 1= .00 >>> =C2=A0=C2=A0=C2=A0 Global reserve:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 512.00MiB=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0 (used: 0.00B) >>> >>> Data,single: Size:490.98GiB, Used:436.04GiB (88.81%) >>> =C2=A0=C2=A0 /dev/mapper/LUKS-RC-cd46b6b4909845918eaa285c532476dc=C2= =A0 490.98GiB >>> >>> Metadata,single: Size:21.01GiB, Used:7.65GiB (36.40%) >>> =C2=A0=C2=A0 /dev/mapper/LUKS-RC-cd46b6b4909845918eaa285c532476dc=C2= =A0=C2=A0 21.01GiB >>> >>> System,single: Size:4.00MiB, Used:80.00KiB (1.95%) >>> =C2=A0=C2=A0 /dev/mapper/LUKS-RC-cd46b6b4909845918eaa285c532476dc=C2= =A0=C2=A0=C2=A0 4.00MiB >>> >>> Unallocated: >>> =C2=A0=C2=A0 /dev/mapper/LUKS-RC-cd46b6b4909845918eaa285c532476dc=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0 0.00B >>> >>> Mount options: >>> /dev/mapper/LUKS-RC-cd46b6b4909845918eaa285c532476dc on /media/btrfs >>> type btrfs >>> (ro,noatime,compress-force=3Dzstd:3,nossd,space_cache=3Dv2,enospc_debu= g,skip_balance,metadata_ratio=3D8,subvolid=3D5,subvol=3D/) >>> >>> btrfs fi df /media/btrfs >>> Data, single: total=3D490.98GiB, used=3D436.04GiB >>> System, single: total=3D4.00MiB, used=3D80.00KiB >>> Metadata, single: total=3D21.01GiB, used=3D7.65GiB >>> GlobalReserve, single: total=3D512.00MiB, used=3D0.00B >>> >>> dmesg attached. >>> >