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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 9C6E4C43331 for ; Tue, 12 Nov 2019 01:02:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5ADDC2184C for ; Tue, 12 Nov 2019 01:02:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="A+2pRRME" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726932AbfKLBCu (ORCPT ); Mon, 11 Nov 2019 20:02:50 -0500 Received: from mout.gmx.net ([212.227.15.19]:42075 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726877AbfKLBCu (ORCPT ); Mon, 11 Nov 2019 20:02:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1573520483; bh=C8O2s6Pg9DeIECtbMxhVUG4s7zeGxSs5e1ITqZ6XaLY=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=A+2pRRME4iEEv9RL+IKRTg+2+I5Yhsq3bR+D2v+ZXuzsFzoj/8pqdxoTajoP2xTmd Ud4Csa7XacWL+GmSM6a7X3Asq07IfMR4uoKwiDtwx8BnNeDZuBZebU6Hpak9tY0grd TapbW1PcpkIRU6wExjdVRr0ONTE1Zzqe1n6D+oyQ= 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 1N9dsV-1hsMYZ1fM5-015YKb; Tue, 12 Nov 2019 02:01:23 +0100 Subject: Re: [PATCH] btrfs: mkfs: Make no-holes as default mkfs incompat features To: dsterba@suse.cz, Qu Wenruo , linux-btrfs@vger.kernel.org References: <20191111065004.24705-1-wqu@suse.com> <20191111180256.GR3001@twin.jikos.cz> 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, 12 Nov 2019 09:01:16 +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: <20191111180256.GR3001@twin.jikos.cz> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="zZYimA061lfdEJZZIUfuA8hjGyhhKhTsI" X-Provags-ID: V03:K1:n6bSDFV8UbcIA9xb6mzpWdhgkLsa7nEILSM+RRfK1EvmAQqd6d5 snk+UNQC+ghhT2XgJgjkUp9UbnpUk3m21f3wvTqQN0cdAC9h7K4EBJwld2l4IJOpBol5bLM Kw0lY4K4oVmCd9uCesXMJ2NpphZMhpD3+C5u4QfxSKIIkTXKiQesehkfxg8ODHAr84Jv1z9 CCoLXlnwH45J0icT0601Q== X-UI-Out-Filterresults: notjunk:1;V03:K0:LDz/PtYAx2w=:hcj0LxdR8aRpsSh4b/UEEO M0CzgojWUbzy3Ocyu1PTFRWhRtudX/KBWcPilzryoN/TPy2BLavnlzJjMgJRyqNKhxnFRNT74 15h+WW3YKnPg3XYsW/cfdg5FLb09rsKxx6sie7YUPSsEa40W1wRVE0aEeCUQZke3HvQMwTtOv nUA8mTDbyzFTbofeb4mr3o0eo8dlF6BQX4uYVGi2J97Ue6DT7CchLaWy56CogyobIW3jfFfqZ rglmgrA+jA2iUlWLj0QIGcW68GmodJs2KiglZh0o8gBgsZp6UrOknqT0CuqMZkcQ8V5Ehl4D7 mEfQDHuVrS6UDsp6CuEATHzjo0jFcMh8lVDGeLYA7A5irBVX/9rpOsSogbKRf0ao4OEoiDClr g9BmDrDN0dVe3eysBfix1vZklpsK+MrTaRsdfD+kLRgwMga6vUlL/kQ+QdnWzP6ZcZVVw2uNQ zfFISq/eMwwfX17NK4f74KwlnM08+DT7w1mWKHGB0Dy3Of77UjDeQI7t5Lcjq/S9LM3Bjo777 wh3IvOngpvP3A3y8Wn1fHmNx2m/cDtQLsxFqx6fQcDu/U6DnTnQhSJVQ6wmGUGOdeykfsosrF A5gWK/1oATMX6C7Gk88AjpX4TAk+igbD0OCITqlsbFE9otwSEc0oqoDGYXGmCWzlqbiZUD0R1 FDwzo/AnK2LZjGTTxI+tStnzontqIZUhq8OC891+fvqPm1ugPmo8Qfig3tOAQIEuDGVwi0DlN 8NI/vedDU0k1XoBQKPMNzS5dQRTQFeYxEMRQF3LBAeMgNfcTAv7MbytChGy/gEaLva9N1hjfu ODxSMuxqMsKJ3XFs1oEG8tnNJ9ENj9Hfcb8Ww3isABep6qOUO6Tku0BSaqiJQncR1DCFtvflr fjn+6q+X8XtA4HGmu+C+heYp39erVX9FgPmwDQwjF6eM7dsRE7ilLgsiNwX2oMUMcHvCSum7P NaQZSeW3I3paVKG574SKCAoOfYonvgJ4ltkcrzMT8xRKb6ApVW1hZq2rnNmeFaG1Dhsx7RhnS 2UPcRzicM6q8DXZa5HYhAV/BQsc6QsmlGtmRUzhP8CAhbRm9nW7e7spENxEEAh018cUoOaY9x O6Hct+71QBk5Vy+LRPThCISRXMEGQ158x8kWBPPpVsiZZfYo3n7Yb0ZqMQausSCWB/aDScFHH ctHb0mem3JBNeqGm5o/taQZmKvMfkin5zq2CnhQnXNe0IlHcfreb820shm5w/hXXyKYDe2WZE NQh/Z/CrS7YqzQWM7Iu5S7vDrlYnwddKoLvjs/3fTFgu3JUPOjesq0n6dEFY= 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) --zZYimA061lfdEJZZIUfuA8hjGyhhKhTsI Content-Type: multipart/mixed; boundary="WRJLP6Gvvo6lfZJRhwRlgGukrcTQBy3bg" --WRJLP6Gvvo6lfZJRhwRlgGukrcTQBy3bg Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2019/11/12 =E4=B8=8A=E5=8D=882:02, David Sterba wrote: > On Mon, Nov 11, 2019 at 02:50:04PM +0800, Qu Wenruo wrote: >> No-holes feature could save 53 bytes for each hole we have, and it >> provides a pretty good workaround to prevent btrfs check from reportin= g >> non-contiguous file extent holes for mixed direct/buffered IO. >> >> The latter feature is more helpful for developers for handle log-write= s >> based test cases. >=20 > Thanks. The plan to make no-holes default has been there for some time > already. What it needs is a full round of testing and validation before= > making it default. And as defaults change rarely, I'd like to add > free-space-tree as mkfs default as well, there's enough demand for that= > and we want to start deprecating v1 in the future. >=20 > I have in my near-top todo list to do that, with the following > checklist: >=20 > - run fstests with various features together + the new default > - release build > - debugging build with UBSAN, KASAN and additional useful debugging > tools Already running with no_holes for several previous releases. Not to mention new btrfs specific log-writes test cases are all already using this feature to avoid btrfs check failure. So I think this part should be OK. > - run stress tests + the new feature Any extra suggestions for the stress test tool? Despite that, extra 24x7 host may be needed for this test. > - check that the documentation covers the change > - mkfs.btrfs help string > - manual page of mkfs.btrfs: benefits, pros/cons, conversion to/from > the feature (if applicable), with example commands (if applicable) > - wiki documentation update Forgot this part. I'll add this info in next update. Thanks, Qu > - verify that all commonly used tools work with it (image, check, tune)= >=20 > For free-space-tree specifically, there's > https://github.com/kdave/drafts/blob/master/btrfs/progs-fst-default.txt= >=20 > I don't have objections to the patch, that's the easy part. The above i= s > non-coding work and is namely making sure that the usecase and usabilit= y > is good, or with known documented quirks. >=20 > Making it default in progs release 5.4 is IMO doable, there are probabl= y > 2-3 weeks before the release, but this task needs one or more persons > willing to do the above. >=20 --WRJLP6Gvvo6lfZJRhwRlgGukrcTQBy3bg-- --zZYimA061lfdEJZZIUfuA8hjGyhhKhTsI Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl3KBFwACgkQwj2R86El /qjTBgf+MIU62lyh/bUPRb782oPBaY9Ml2EGRpFdBt6Z6D99/K4xml0Rr6I9hCMS qekWjXSStW/sRef4H3O/wwQmW0xSgLfAA05HyXbi9vpdw9hbP8N8BPrT/8eMsZcW ldUa3sd1IXKMCSrPeoF8b5IQAvXO9MclYinGQP979o73L25UBPtK1Yjg3iGjbxuB JJQxlGvv/qrZhvlw5G9R7zcsDIO+f8WYntA1T3CxXQ8YC5TXbPqe8CHG5iRbC+ka ge83PITitw/v+nt2DdEnguQLuBJFGIxhxnD0JaYzczL4D1GM0JBQVHMytfylkjvg 0aKRPRqKyavnYBLo3gTof2CgSjTy9w== =xMMu -----END PGP SIGNATURE----- --zZYimA061lfdEJZZIUfuA8hjGyhhKhTsI--