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=-2.3 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, URIBL_BLOCKED,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 1E488C43332 for ; Sun, 22 Mar 2020 08:35:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AE2AB206F8 for ; Sun, 22 Mar 2020 08:35:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=inwind.it header.i=@inwind.it header.b="gfQVP74e" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726864AbgCVIeL (ORCPT ); Sun, 22 Mar 2020 04:34:11 -0400 Received: from smtp-32.italiaonline.it ([213.209.10.32]:33327 "EHLO libero.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726770AbgCVIeL (ORCPT ); Sun, 22 Mar 2020 04:34:11 -0400 Received: from venice.bhome ([84.220.24.82]) by smtp-32.iol.local with ESMTPA id Fw3bjt71oa1lLFw3bjztI9; Sun, 22 Mar 2020 09:34:08 +0100 x-libjamoibt: 1601 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=inwind.it; s=s2014; t=1584866048; bh=GXWmhSS3O6XLw62j55lJ0/g0BQJ4jSS4mZcQ4kYxcd0=; h=From; b=gfQVP74e1FtLXhWggZbwJq7CK4HJ/L1YjTc8ADO5eSn9fNMZWlyl/9N2Ec/l8xY1m pSVLiWlQ2N4tOfG6ffdfGHODzV/WpFGlWsvKvM/TVQmGErid8s4iaAGSQrtGTPWhyG +2Z62IwgWfMwUCQjm4dtTfyjnO7UjY+937IW1WWe2/8qHPaxF54lVD8/PPAxp2yjBI 95C4uXdlraVvkw6Kx0gXQdqDEHzr+hvH2gDIJiltDJujt63QtNbyN531wRFgY1LsTs iaor5TleBOstyrHTGNy+8pfMB7lZOPqi0sZtZD6j72MJh5Fp1cyGUukm03IyDsJm7k Gn3ATWriWkF/Q== X-CNFS-Analysis: v=2.3 cv=IOJ89TnG c=1 sm=1 tr=0 a=ijacSk0KxWtIQ5WY4X6b5g==:117 a=ijacSk0KxWtIQ5WY4X6b5g==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=IkcTkHD0fZMA:10 a=6fIKVRZl-Jdao0fNtgkA:9 a=QEXdDO2ut3YA:10 Reply-To: kreijack@inwind.it Subject: Re: Question: how understand the raid profile of a btrfs filesystem To: Zygo Blaxell Cc: linux-btrfs References: <517dac49-5f57-2754-2134-92d716e50064@alice.it> <20200321032911.GR13306@hungrycats.org> <20200321232638.GD2693@hungrycats.org> From: Goffredo Baroncelli Message-ID: <3fb93a14-3608-0f64-cf5c-ca37869a76ef@inwind.it> Date: Sun, 22 Mar 2020 09:34:07 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200321232638.GD2693@hungrycats.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfA1nHjAtRhCAmdHz2286QIoSpNtYySAwMqJn6wUJ2tXpiaZ2tiMS/uchUcX334TH1SaC/6vN2DidRSF24z/C0uzAE3Nr+01gD95DWNf5Y+vma2BEOG3V KRn4FcDdMuZRFxkT3MVybghZjP/1TuWJB9PAcP0bpbqwVkjRk9ccR6/6p+HKg3/2VECUwxFczh1wa3KG8w+pfYZywA8IeQq0u1cYBq4iqL/0nshPpT4plg7b Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Hi Zygo, On 3/22/20 12:26 AM, Zygo Blaxell wrote: > On Sat, Mar 21, 2020 at 10:55:32AM +0100, Goffredo Baroncelli wrote: >> On 3/21/20 4:29 AM, Zygo Blaxell wrote: >>> On Fri, Mar 20, 2020 at 06:56:38PM +0100, Goffredo Baroncelli wrote: >>>> Hi all, >>>> [...] > ...but now you are not running conversion any more, and have multiple > profiles. It's not really specified what will happen under those > conditions, nor is it obvious what the correct behavior should be. > > The on-disk format does not have a field for "target profile". Ok, I looked for a confirmation of that. > Adding one would be a disk format change. Yes but I think that it would be done in a backward compatible way. I think to add a field "target profile" in the super-block. The old kernels will ignore this field, and behave as today. The new ones will allocates the new chunk according to this field. To me it seems complicated to Any thoughts ? BR G.Baroncelli -- gpg @keyserver.linux.it: Goffredo Baroncelli Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5