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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5A4B8C433EF for ; Thu, 26 May 2022 16:15:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345463AbiEZQPO (ORCPT ); Thu, 26 May 2022 12:15:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240675AbiEZQPL (ORCPT ); Thu, 26 May 2022 12:15:11 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D69C96A056 for ; Thu, 26 May 2022 09:15:10 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 328901F8CB; Thu, 26 May 2022 16:15:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1653581709; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=31BJfVyvlu20Gtk4zJPEKiNQGYXg9ttwh0osyYG/sH0=; b=v79d6BDIqUf/eGULtZ5vI9wkdsSfvmvryR8o72QbHIGZQ7Ccp+cID2mRt0gIpBRGdDZhxe Nw31R1Zn9kBNo7WeuuFjPqNfSwLx3KBSf6IdieFJyI/kwwj3A717x4zoE9ZcjduvD9rv1j cjAwG9CXSgYkXhjxnijRUDZo3p39mVA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1653581709; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=31BJfVyvlu20Gtk4zJPEKiNQGYXg9ttwh0osyYG/sH0=; b=pQDPR12b7b0vbIZWQmG3hwxs9oTJ/K33Ihy2TTYErKWBXTM+MT39CSTyhPQ12mn/CKdeXF wVmcblr+oZmUuUBA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id ED91213AE3; Thu, 26 May 2022 16:15:08 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id F4/XOIynj2KxIwAAMHmgww (envelope-from ); Thu, 26 May 2022 16:15:08 +0000 Date: Thu, 26 May 2022 18:10:45 +0200 From: David Sterba To: kreijack@inwind.it Cc: Qu Wenruo , waxhead@dirtcellar.net, Christoph Hellwig , dsterba@suse.cz, Qu Wenruo , linux-btrfs@vger.kernel.org Subject: Re: [PATCH DRAFT] btrfs: RAID56J journal on-disk format draft Message-ID: <20220526161045.GH22722@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, kreijack@inwind.it, Qu Wenruo , waxhead@dirtcellar.net, Christoph Hellwig , Qu Wenruo , linux-btrfs@vger.kernel.org References: <20220524170234.GW18596@twin.jikos.cz> <9d1e2fc6-9ee6-68f8-bda8-8dd7e59e74e5@dirtcellar.net> <50cb070b-2e2e-1987-3726-1e67eaf060cf@gmx.com> <4fde1fb7-b6ea-c6e5-7c04-f6c19e031354@libero.it> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4fde1fb7-b6ea-c6e5-7c04-f6c19e031354@libero.it> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Thu, May 26, 2022 at 05:30:16PM +0200, Goffredo Baroncelli wrote: > On 26/05/2022 11.26, Qu Wenruo wrote: > [...] > > > > Deprecation needs time, and RAID56J is not a drop-in replacement > > unfortunately, it needs on-disk format change, and is new RAID profiles. > > > IIRC, the original idea was to dedicate a separate disk to the journal. And was rejected as it would be the single point of failure for drive setup that must survive failure of 1 or 2 devices.