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=-3.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM, RP_MATCHES_RCVD shortcircuit=no autolearn=no 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 AFE7F20286 for ; Fri, 15 Sep 2017 11:24:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751269AbdIOLYw (ORCPT ); Fri, 15 Sep 2017 07:24:52 -0400 Received: from mail-it0-f45.google.com ([209.85.214.45]:51497 "EHLO mail-it0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751207AbdIOLYv (ORCPT ); Fri, 15 Sep 2017 07:24:51 -0400 Received: by mail-it0-f45.google.com with SMTP id o200so3227349itg.0 for ; Fri, 15 Sep 2017 04:24:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=qF6fGo1e78Waoqr4pdFR/C2HjLg0vQqtkxEhXUfTpcg=; b=iMQmORYtGMAUPyCcpi+cckk3p2zxayhog9DJOb8swwGKKgxouOdckgTjfX9uI8KMJe jLaYCxB4sAeRe29VKu9fpohLD+ZEu0j02YyLVNAZKfPSuoAkfpXevOHVKQHc2vcNPHMt 7EmNZsX2VFZ9nf/G3/hGvNgzY+9sjzXg26NRIDbcFtxVR0gF/nBihOTYrusNVOzwufIo Mrvj2MT0hcGjOdaKEUpJx8x9lciAcRd6dDkpg2yh+5Ezpkl8ML4FzhmNMAhoKXuaru01 O2Br+NtDmugwuH7LM2MNdLuhPt8VSeGw3W7eJzjW7D6JEP44rxS/ytlJwyfwz92TNjs+ vp3g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=qF6fGo1e78Waoqr4pdFR/C2HjLg0vQqtkxEhXUfTpcg=; b=hFIEAQ6exKtouIZH6lGCVf9mgEZiJjvJpAzLWpJpQB9migVWIH3Iya4rnSJlre+GQW +5qC0DP4jDspMODxadEvBXQthawmlkv8A9qlrPqhQQn1R0S7KvuWWUkXLIJkVPy+V6+e dMnlyqyVSwPsCnB+yo9Yq0IBe1Ep4V8UZjIlyIXQwC9DrUBApaW/aBH1Puv+H1EYjm5a TLPAc2Kis4jJxoxWD6a3tNZUrUdaGhab8kVi4f4Wc2qVeV+ryJ7GpMkPx/mj526Mxs8v mWwsyGnNiKeySTddw+i81qjCS3tdKsZxf8gWjtghLpGhLT1d2+wCOwwcKQwvMNEx0QVe KTXA== X-Gm-Message-State: AHPjjUhiQsyEJtMVtvDt2+KynELzmDxxoxsBuMynU2x5CCaLuJQc2XrO KXhm7GxyE5gI8/4WS8ok4kw/6txBzRwhDMBXPk0= X-Google-Smtp-Source: AOwi7QDaXkP51qkaKV+qsn2FgUt9RA2uBZJ41FbuSNk6tOEiE3b5Kj3crca3VWZcDU2yBr6/ol6BHzwJnjCM9opkSjc= X-Received: by 10.36.185.12 with SMTP id w12mr4609274ite.67.1505474690974; Fri, 15 Sep 2017 04:24:50 -0700 (PDT) MIME-Version: 1.0 Received: by 10.79.107.136 with HTTP; Fri, 15 Sep 2017 04:24:50 -0700 (PDT) In-Reply-To: <20170914111945.62741763@twelve2.svl.corp.google.com> References: <20170803091926.1755-1-chriscool@tuxfamily.org> <20170803091926.1755-26-chriscool@tuxfamily.org> <20170914111945.62741763@twelve2.svl.corp.google.com> From: Christian Couder Date: Fri, 15 Sep 2017 13:24:50 +0200 Message-ID: Subject: Re: [PATCH v5 25/40] external-odb: add 'get_direct' support To: Jonathan Tan Cc: Junio C Hamano , git , Jeff King , Ben Peart , Nguyen Thai Ngoc Duy , Mike Hommey , Lars Schneider , Eric Wong , Christian Couder Content-Type: text/plain; charset="UTF-8" Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Thu, Sep 14, 2017 at 8:19 PM, Jonathan Tan wrote: > On Thu, 14 Sep 2017 10:39:35 +0200 > Christian Couder wrote: > >> From the following email: >> >> https://public-inbox.org/git/20170804145113.5ceafafa@twelve2.svl.corp.google.com/ >> >> it looks like his work is fundamentally about changing the rules of >> connectivity checks. Objects are split between "homegrown" objects and >> "imported" objects which are in separate pack files. Then references >> to imported objects are not checked during connectivity check. >> >> I think changing connectivity rules is not necessary to make something >> like external odb work. For example when fetching a pack that refers >> to objects that are in an external odb, if access this external odb >> has been configured, then the connectivity check will pass as the >> missing objects in the pack will be seen as already part of the repo. > > 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/ > (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.