From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.2 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id C60D120281 for ; Fri, 15 Sep 2017 20:54:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751676AbdIOUy4 (ORCPT ); Fri, 15 Sep 2017 16:54:56 -0400 Received: from mail-pg0-f42.google.com ([74.125.83.42]:47152 "EHLO mail-pg0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751556AbdIOUyz (ORCPT ); Fri, 15 Sep 2017 16:54:55 -0400 Received: by mail-pg0-f42.google.com with SMTP id d8so2160961pgt.4 for ; Fri, 15 Sep 2017 13:54:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=q+45i+PAel8g97yGYKXJ1GTAEEB3IncfPP6gF5KHVs8=; b=AXZF3bjxZHgaojquS+YSj/c8SVTvoJDI6PZPrgxDmzoCkaCWWLGR9OWoU0ka+oIedc FFE9ro/zJsGetJrbpOoZx9lXsK8ehbjFuAfBH6AwFD90x25ZfmO+T5DelOIRXV1E1+Va E97u52v0Sz57qgc5955Jmn6sTd9pADkfOxaG602HS3d3hXeAOaW339s+gFghmAcW+ZS4 ngAI1SHID5kRD5lo/O1f/dxcl/ZJbkMATwWHAL9L7Q+WI3zgSZbqaikJIOETilJ07Fo6 o6z5TTVt/cY9+M5l7P9+z64szKl4ua1PRCZvrTGqq91p/xvQhLzDiAramnQtYXWAWDkR o/vw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=q+45i+PAel8g97yGYKXJ1GTAEEB3IncfPP6gF5KHVs8=; b=dXHMxYiYaF/d1+MM6BWw14sojlhW3XFr3bacGnrPQdTYVUDh/zU7SAEgWQEHmLnUUu 4fEenx5ChkYWwUOwBfGWw00m71Gnp2uF4M10TB+e+DOsn4lxs0sQpeUVig7brQZjIoEP L8d41kc0f2fLjBWVHrQTxU4FbnNuaokyrAjlTwMjuuA3hnqbcw4oScGCsMiXX8MXXpb3 OGNLv731x0zFWh6EDPcbDmTfV99F0vtdC1Fp1IA+hwwDRng34uKueW17wtz4MXMEROgK L/auopyV3hmlgU7Ae0iwpzxPajL6+IQ29hSaCLc5t04dmWDURGKnWVWkF0fUJtizmjtk oFrQ== X-Gm-Message-State: AHPjjUhpgidwACvrj0qUTftveMSJi6/aDFy83louq+R1McJ3cqVQWN7V pn7HztYFh8Z+Q2f9 X-Google-Smtp-Source: ADKCNb6ZN8KuRz3I5gc5/Kaf18D0fts4ANWbyKALNaa26B1uv/Dd9nkZ0/Sv4lg6EmoVKt31SJtsWA== X-Received: by 10.98.219.6 with SMTP id f6mr25828737pfg.59.1505508895000; Fri, 15 Sep 2017 13:54:55 -0700 (PDT) Received: from twelve2.svl.corp.google.com ([2620:0:100e:422:48c5:a795:146c:44c6]) by smtp.gmail.com with ESMTPSA id b66sm3179848pgc.29.2017.09.15.13.54.54 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Fri, 15 Sep 2017 13:54:54 -0700 (PDT) Date: Fri, 15 Sep 2017 13:54:52 -0700 From: Jonathan Tan To: Christian Couder Cc: Junio C Hamano , git , Jeff King , Ben Peart , Nguyen Thai Ngoc Duy , Mike Hommey , Lars Schneider , Eric Wong , Christian Couder Subject: Re: [PATCH v5 25/40] external-odb: add 'get_direct' support Message-ID: <20170915135452.4289d591@twelve2.svl.corp.google.com> In-Reply-To: References: <20170803091926.1755-1-chriscool@tuxfamily.org> <20170803091926.1755-26-chriscool@tuxfamily.org> <20170914111945.62741763@twelve2.svl.corp.google.com> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Fri, 15 Sep 2017 13:24:50 +0200 Christian Couder wrote: > > There are still some nuances. For example, if an external ODB provides > > both a tree and a blob that the tree references, do we fetch the tree in > > order to call "have" on all its blobs, or do we trust the ODB that if it > > has the tree, it has all the other objects? In my design, I do the > > latter, but in the general case where we have multiple ODBs, we might > > have to do the former. (And if we do the former, it seems to me that the > > connectivity check must be performed "online" - that is, with the ODBs > > being able to provide "get".) > > Yeah, I agree that the problem is more complex if there can be trees > or all kind of objects in the external odb. > But as I explain in the following email to Junio, I don't think > storing other kind of objects is one of the most interesting use case: > > https://public-inbox.org/git/CAP8UFD3=nuTRF24CLSoK4HSGm3nxGh8SbZVpMCg7cNcHj2zkBA@mail.gmail.com/ If we start with only blobs in the ODB, that makes sense (the ODB will need to supply a fast enough "list" or "have", but, as you wrote before, a mechanism like fetching an additional ref that contains all the necessary information whenever we fetch refs would be enough). I agree that it would work with existing use cases (including yours). > > (Also, my work extends all the way to fetch/clone [1], but admittedly I > > have been taking it a step at a time and recently have only been > > discussing how the local repo should handle the missing object > > situation.) > > > > [1] https://public-inbox.org/git/cover.1499800530.git.jonathantanmy@google.com/ > > Yeah, I think your work is interesting and could perhaps be useful for > external odbs as there could be situations that would be handled > better using your work or something similar. Thanks.