From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-124.freemail.mail.aliyun.com (out30-124.freemail.mail.aliyun.com [115.124.30.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 437322AE84; Fri, 27 Sep 2024 02:18:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727403494; cv=none; b=cZ5G7nLIqV216INBjpE86FFbonqnIge2Kcgnlp34yZph8K9MRel+LqSJ0514/xQAPoreMGGts68LooPEBJ+L6n8K0hvPvKQkWHVRIwbTod6zqwSr1ovc1cjFMati9sxt4aeCfL5ysqCtN4RioeIdy30g807+6epvILmLKjQlyig= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727403494; c=relaxed/simple; bh=Q8XmPJ4iAfsRaKmreIHD8vW7v2ivqKMnyBTMhAdDPfA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Uj4+XHTm4bsYT72bAD9oftFkLvOnwRGaIQkBv0ypRle5vRzdVP46KEiSt6iJ1ggl8JI7jPRaoJIDHrmihBcRMabOUX30EWfaRE5z2Y/UskL8eD6x6LEmu3VR68vCuDarjLpwo2psfGkHK96Q55gHR87M76Jchkvrtdn2Y3IX0Kk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=Ow5/E/yV; arc=none smtp.client-ip=115.124.30.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="Ow5/E/yV" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1727403489; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=/r/tjBNR+IWRjvp0HptBoGnx5lgEQTTKVUb3akceKm8=; b=Ow5/E/yVKmhtIML0B8j1g1GcM0yBq5hqnUT1JSsGDf5eiLNarO6qjvxXnYNMXsPoPc5Rrq3KqCC1QkC8d5xdqNiAok/s/ncj5DbqvjSzsmaNY2Cfy7dEn4+K2Cyn+vS+G3fqYWUBfaGG7aOgf/Mxf3hog9+5oEt35rpda4WCOsE= Received: from 30.244.152.118(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WFokCVX_1727403487) by smtp.aliyun-inc.com; Fri, 27 Sep 2024 10:18:08 +0800 Message-ID: <7739346c-b98e-4359-b0d2-44cd73ae55f0@linux.alibaba.com> Date: Fri, 27 Sep 2024 10:18:06 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 03/24] erofs: add Errno in Rust To: Ariel Miculas Cc: Benno Lossin , rust-for-linux@vger.kernel.org, Greg Kroah-Hartman , LKML , Linus Torvalds , Al Viro , Gary Guo , linux-fsdevel@vger.kernel.org, linux-erofs@lists.ozlabs.org References: <80cd0899-f14c-42f4-a0aa-3b8fa3717443@linux.alibaba.com> <20240925214518.fvig2n6cop3sliqy@amiculas-l-PF3FCGJH> <0ca4a948-589a-4e2c-9269-827efb3fb9ef@linux.alibaba.com> <20240926081007.6amk4xfuo6l4jhsc@amiculas-l-PF3FCGJH> <54bf7cc6-a62a-44e9-9ff0-ca2e334d364f@linux.alibaba.com> <20240926095140.fej2mys5dee4aar2@amiculas-l-PF3FCGJH> <5f5e006b-d13b-45a5-835d-57a64d450a1a@linux.alibaba.com> <20240926110151.52cuuidfpjtgwnjd@amiculas-l-PF3FCGJH> <20240926124959.n7i33p4fonp2op27@amiculas-l-PF3FCGJH> From: Gao Xiang In-Reply-To: <20240926124959.n7i33p4fonp2op27@amiculas-l-PF3FCGJH> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2024/9/26 20:50, Ariel Miculas wrote: > On 24/09/26 07:23, Gao Xiang wrote: ... >>> >>> It might be a fair comparison, but that's not how container images are >>> distributed. You're trying to argue that I should just use EROFS and I'm >> >> First, OCI layer is just distributed like what I said. >> >> For example, I could introduce some common blobs to keep >> chunks as chunk dictionary. And then the each image >> will be just some index, and all data will be >> deduplicated. That is also what Nydus works. > > I don't really follow what Nydus does. Here [1] it says they're using > fixed size chunks of 1 MB. Where is the CDC step exactly? Dragonfly Nydus uses fixed-size chunks of 1MiB by default with limited external blobs as chunk dictionaries. And ComposeFS uses per-file blobs. Currently, Both are all EROFS users using different EROFS features. EROFS itself supports fixed-size chunks (unencoded), variable-sized extents (encoded, CDC optional) and limited external blobs. Honestly, for your testload (10 versions of ubuntu:jammy), I don't think CDC made a significant difference in the final result compared to per-file blobs likewise. Because most of the files in these images are identical, I think there are only binary differences due to CVE fixes or similar issues. Maybe delta compression could do more help, but I never try this. So as I asked in [1], does ComposeFS already meet your requirement? Again, EROFS could keep every different extent (or each chunk, whatever) as a seperate file with minor update, it's a trivial stuff for some userspace archive system, but IMO it's controversal for an in-tree kernel filesystem. [1] https://github.com/project-machine/puzzlefs/issues/114#issuecomment-2369971291 Thanks, Gao Xiang