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 124DFC7EE2D for ; Fri, 26 May 2023 10:29:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242150AbjEZK3x (ORCPT ); Fri, 26 May 2023 06:29:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243253AbjEZK3r (ORCPT ); Fri, 26 May 2023 06:29:47 -0400 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C4C501A8 for ; Fri, 26 May 2023 03:29:43 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R281e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046051;MF=durui@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0VjW43MX_1685096980; Received: from localhost(mailfrom:durui@linux.alibaba.com fp:SMTPD_---0VjW43MX_1685096980) by smtp.aliyun-inc.com; Fri, 26 May 2023 18:29:41 +0800 From: Du Rui To: gscrivan@redhat.com Cc: agk@redhat.com, alexl@redhat.com, dm-devel@redhat.com, durui@linux.alibaba.com, hsiangkao@linux.alibaba.com, linux-kernel@vger.kernel.org, snitzer@kernel.org Subject: Re: Re: dm overlaybd: targets mapping OverlayBD image Date: Fri, 26 May 2023 18:28:56 +0800 Message-Id: <20230526102855.36774-1-durui@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <87r0r6ywri.fsf@redhat.com> References: <87r0r6ywri.fsf@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Giuseppe, > The current OCI format, with some tweaks like (e)stargz or zstd:chunked, > already make its content addressable and a client can retrieve only the > subset of the files that are needed. At the same time we maintain the > simplicity of a tarball and it won't break existing clients. Yes, I believe backward compatibility is very important. That's why we have another design called foci (fast oci). It realize a virtual block device from gzip image blobs. See the following link for details if interested. https://github.com/containerd/accelerated-container-image/blob/main/docs/FASTOCI.md