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=-2.0 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 7D4ABC43603 for ; Thu, 5 Dec 2019 03:26:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C1A52073B for ; Thu, 5 Dec 2019 03:26:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="XX2TXfZT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728490AbfLED0j (ORCPT ); Wed, 4 Dec 2019 22:26:39 -0500 Received: from mout.gmx.net ([212.227.15.19]:37269 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728321AbfLED0j (ORCPT ); Wed, 4 Dec 2019 22:26:39 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1575516387; bh=62w2zF6h6VefZJkTnxLpNB4hf+UEOVNJwgeWJT4SOxs=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=XX2TXfZTs+S7UifGNoIzJcRuMMw99QRxRKsGFYT8OH9UsOsF1zcZtBWeq8uSHQP2u guOfmoJy6+9yvV0MWlvPymHnwlfdkELg2OgtZsZiA/iZ32LaSCtupBjeuWemUTIFlK qLaw/v96f+0YejHKxH/Yfv52jAv+R+opZuOuw+WQ= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([13.231.109.76]) by mail.gmx.com (mrgmx005 [212.227.17.184]) with ESMTPSA (Nemesis) id 1MTABZ-1iBvYb3wJ5-00UaYf; Thu, 05 Dec 2019 04:26:27 +0100 Subject: Re: [PATCH 0/4] btrfs: Make balance cancelling response faster To: Zygo Blaxell , Qu Wenruo Cc: linux-btrfs@vger.kernel.org References: <20191203064254.22683-1-wqu@suse.com> <20191205025832.GY22121@hungrycats.org> 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: <99b2e889-df1d-7302-6076-42c643221a27@gmx.com> Date: Thu, 5 Dec 2019 11:26:20 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20191205025832.GY22121@hungrycats.org> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="9M8ypIQPVR8rwW3fRamQcM1wfPgNqtRgp" X-Provags-ID: V03:K1:2ezTKV/WYKf0G01ACH5QNyINSaxTr7EPV4knda2ijk1FOtWYkST IIGjrKnOqXNxEvc+yZAsulKS2NdfJG68gWfHoG2uGcDPFkdNKQcBpp8XAxdkfR8OuzvSnh5 MYXlwNV/igd8qHUn1V3iZ2NiK4gVq61/5hp8I9thzFSc2cN7WeWdGn2abwFOldsavXg/vq1 KH9WksjHncFcx/MZRDSYw== X-UI-Out-Filterresults: notjunk:1;V03:K0:nicBBlzdwCM=:fYVd1CnfBtZbQ+A8t5BohZ t2zXwpgCHjdbacx1ht8C1xFa7HDrDtg36QqHShoVWAXuux5BWwcgJD/T2Dey4cPc1r699i+9b 4fZYiD8Nw7TbsJi7DUGesq1ffOzL+TcF1z+YHSCCC051bwffLxcaTZC6LhMLsfQ+WvohbzqvY 0YuN6sqokSEAak0dKRAFGx63lWHHUs2p/M8n4xh4o/7IqMNpPYCZ1C63WDWDadPgRtDGa/rTg JPCsCaZxEJJEk/VYfLjujU0qSncryX/vjxY3YqO7HmtaVU6uWWKsCvcQKB+xbOzFcwrgNh/5o CtpKqUCuXYcJWZ16mr1dMq3JC5PvhfPcrPggeD4GVQbsu41W+sB4YWHKjSCM/iaDLNQ0TJonf 5ZYlPYb8b5kjDIZl/szWxN14WrWVVCr3g3iZa2eTkPqGzcuc9B22qTOgYxoq451HAHx1PM47H xQkTbKrzNMFyvsfXt4ACb6fX1sBN9nWuaz7+JI7Lz/LoqOyp+0AzY6sV/aPHj/qBuuF4pPjNP lIZjtpLC+KU0NvfIy9EOYd1/uMChsQGrwF6D28wVbN3LQ+pp18cQStAGOtTuh9iTq/fPRNCRc VvEWLWzsjTcgcLH2p76T14YziOmcjcl3GqJPvgOm1BxEpj8NnLkPBZlgpNldV5u9o9NSi/L8u +6n+hW8T/PrinqxvgY10ahTcxzMSBSe5K4pEL/7g1WRY3jftaSOzqF3Y/eVmBa5yc4Bt11m1L 4Ap2BuRm60VY1r+6CWuUzxgP0JWysbmE36aNEb1eXwcMpP2ovBQuUjsk3XOwrzs+V2kWH+AWe jLpVg1jcZm3Nd5X3veqPRwBXUp3r2uDfzVuvYSFwRQn1DSCZhGwG1KPBG8ZdTu2ZAvN4Lzss2 3ghKQRRc3yUYOXHsq+UuWJFsuoQYhrl3N38GzOq6Fc3KOILpa9VFsC5KAtkK9SIIbNCczk1Xe QsqPH7ZkcOpH5cRhx3tNX2DvmDzAIE46kDULVPbxUMNnzSv/WaAqaMut+iKMq7Y6CnuPdAKjh ZCFAYZihOBLkref+Hs0uiA0QLGrCm8FoeKAz7f9OubKcpkSvNcn5gjBTC0VF0SOVaYYdcvFuA ZgSESdyP5vfeJDfzsYvJIa4jPNqcbeXRJCccgByHcK3o3RDLyYnso+8ZCy+PRtrr7gYkI+vr0 xbsUpmp9BT6hy2s6ND3RhTVG4Pg6WCIQ5FlEwHj4bg64XWbZ4tBcqyxdZEt9TkAQP/iQJpNzR MxHs0PjLGBDs2CXmiYutYXLDqDAkbnwRJZ2WQorG0wYmkghwhk6ko5c640zo= Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --9M8ypIQPVR8rwW3fRamQcM1wfPgNqtRgp Content-Type: multipart/mixed; boundary="hOSRsj9JK9XO312uHDqhDflJbCgAvb3fF" --hOSRsj9JK9XO312uHDqhDflJbCgAvb3fF Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2019/12/5 =E4=B8=8A=E5=8D=8810:58, Zygo Blaxell wrote: > On Tue, Dec 03, 2019 at 02:42:50PM +0800, Qu Wenruo wrote: >> [PROBLEM] >> There are quite some users reporting that 'btrfs balance cancel' slow = to >> cancel current running balance, or even doesn't work for certain dead >> balance loop. >> >> With the following script showing how long it takes to fully stop a >> balance: >> #!/bin/bash >> dev=3D/dev/test/test >> mnt=3D/mnt/btrfs >> >> umount $mnt &> /dev/null >> umount $dev &> /dev/null >> >> mkfs.btrfs -f $dev >> mount $dev -o nospace_cache $mnt >> >> dd if=3D/dev/zero bs=3D1M of=3D$mnt/large & >> dd_pid=3D$! >> >> sleep 3 >> kill -KILL $dd_pid >> sync >> >> btrfs balance start --bg --full $mnt & >> sleep 1 >> >> echo "cancel request" >> /dev/kmsg >> time btrfs balance cancel $mnt >> umount $mnt >> >> It takes around 7~10s to cancel the running balance in my test >> environment. >> >> [CAUSE] >> Btrfs uses btrfs_fs_info::balance_cancel_req to record how many cancel= >> request are queued. >> However that cancelling request is only checked after relocating a blo= ck >> group. >> >> That behavior is far from optimal to provide a faster cancelling. >> >> [FIX] >> This patchset will add more cancelling check points, to make cancellin= g >> faster. >=20 > Nice! I look forward to using this in the future! >=20 > Does this cover device delete/resize as well? Shrink also takes use of balance, so I see no reason why it won't work on such use cases. > I think there needs to be > a check added for fatal signals for those to work, as they don't respon= d > to balance cancel. That's a good extra idea. Since we have that wrapper, it would be easier to add in the future. Thanks, Qu >=20 >> And also, introduce a new error injection points to cover these newly >> introduced and future check points. >> >> Qu Wenruo (4): >> btrfs: relocation: Introduce error injection points for cancelling >> balance >> btrfs: relocation: Check cancel request after each data page read >> btrfs: relocation: Check cancel request after each extent found >> btrfs: relocation: Work around dead relocation stage loop >> >> fs/btrfs/ctree.h | 1 + >> fs/btrfs/relocation.c | 23 +++++++++++++++++++++++ >> fs/btrfs/volumes.c | 2 +- >> 3 files changed, 25 insertions(+), 1 deletion(-) >> >> --=20 >> 2.24.0 >> --hOSRsj9JK9XO312uHDqhDflJbCgAvb3fF-- --9M8ypIQPVR8rwW3fRamQcM1wfPgNqtRgp Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl3oeNwACgkQwj2R86El /qgBiQf+PRLbeaNFzuMDGChGb/n9Rx02DnXKXyAdwzU/+jXqeObnCoD8lEMtPIwj iC0NmeNmRwlN9teWN4XT9sui7ibScWppblH34MCP7OXzafq215e/yef0bWfVpzef 3mH+BQ1HsBG62OLc/Lq6L467CLhMzvqg5+U2ELpLnTSAVpdIFLJbLtfoRrBbVeQC C21jcc59j64EQbUVSIrKhCV5zwD41VoBwrY1HYN/VW2HMTGwDp/5Lw1FfxQ670er 4c3n8mNxYjazN1kaZ6QJ1fcvacQQXoKsTUF5j8dZRm8Ifmfb2xpQwKKBLP7gZAIG lmcbhzSfuSvrXK+Iwzp1n3F4CrhIRQ== =xZks -----END PGP SIGNATURE----- --9M8ypIQPVR8rwW3fRamQcM1wfPgNqtRgp--