From patchwork Tue Apr 14 04:04:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taylor Blau X-Patchwork-Id: 11486695 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0DECD81 for ; Tue, 14 Apr 2020 04:04:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E5F3B20737 for ; Tue, 14 Apr 2020 04:04:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ttaylorr-com.20150623.gappssmtp.com header.i=@ttaylorr-com.20150623.gappssmtp.com header.b="WsH7/9Z4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405067AbgDNEEP (ORCPT ); Tue, 14 Apr 2020 00:04:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726058AbgDNEEN (ORCPT ); Tue, 14 Apr 2020 00:04:13 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D575BC0A3BDC for ; Mon, 13 Apr 2020 21:04:11 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id z9so4684180pjd.2 for ; Mon, 13 Apr 2020 21:04:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ttaylorr-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=pnmstrq41vvkwasQvJo9GppKN9vte6zAsQ24x/vm4nQ=; b=WsH7/9Z4i1vVES0OsDVOmvJ3FpYioR0Ji/nt2PKMKqYQdyWIImkpq9AaoIeBhY2j61 JS8RIBKiJmM66a45gdCWwxtGxZZ9i+JSEb2m4fd+/Q1D/yjjIxDjo4pBVLc62MmKKPGb UBVq0IsL/HoLFnN1v1SdPo0NHkXjgxdENIuU/RLIZaieNGr5jF79p4efQSjsL8xI5d6j bMvSKzmxjhZy6hImT6e8y8CCSJUy9SVU2SGrLUuVPJdrqPy+kHOHrG7UUXnz0tkhZDib TSFxxk2I1Gn5bSQJlHOLfE3QIGDs32FzhRNGU7hQHWnwMwTMoMBJIJPnUNmw11hLnXYL WgBw== 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:references :mime-version:content-disposition:in-reply-to; bh=pnmstrq41vvkwasQvJo9GppKN9vte6zAsQ24x/vm4nQ=; b=GSiQIMCcX9N2mgJlSBRMQ59ZMizhPQ7nX+ekRBpMJu7ddNmYXwKTbAvQ5L8H0ufKTC pESQ8XlMC55bo96pZe0vWGqspSXpnX7X8HpFviHhQLwnWuZZ2HRtNBgUI7uGDD/+Nl5X /B2y6gCcj+nqBfW7+3vCLNhW9Y4LC3+/z4pGZ3GqbXuWoAftR3MS3Qcn0GLU/Gm+9wxC YIo2GxaFr816RjWv6TPbKJLOhG8nfGpo4UfghWI1qk0ZuekmV3aHrsRgXSzO1MfmDGh8 gda2Yo1fN6cqdBg+xzjQMse8g6JYJ6xmxFl4zgdaDASBGvGjJv/3E2be1DIQY+A/vJ4w nZqA== X-Gm-Message-State: AGi0PuauAbLehkQNQmSafzgvFIq1eg6Io5lM9Q2zBkQOKeIHw5Q37DB8 c/x2twXdEY+kYT6YpNs/tXMhHOiV88eD0Cuf X-Google-Smtp-Source: APiQypL9rZUrm5DCWIT/4pF3rZFUboK16xSZClu2S1WwwGziqMQvuS9Tj5bxeIQjENE07PpTH7xr0w== X-Received: by 2002:a17:90a:30e7:: with SMTP id h94mr23583661pjb.186.1586837050487; Mon, 13 Apr 2020 21:04:10 -0700 (PDT) Received: from localhost ([8.44.146.30]) by smtp.gmail.com with ESMTPSA id x4sm9971526pfa.191.2020.04.13.21.04.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 21:04:09 -0700 (PDT) Date: Mon, 13 Apr 2020 22:04:08 -0600 From: Taylor Blau To: git@vger.kernel.org Cc: dstolee@microsoft.com, gitster@pobox.com, martin.agren@gmail.com, peff@peff.net, szeder.dev@gmail.com Subject: [PATCH 2/7] builtin/commit-graph.c: support for '--split[=]' Message-ID: References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org With '--split', the commit-graph machinery writes new commits in another incremental commit-graph which is part of the existing chain, and optionally decides to condense the chain into a single commit-graph. This is done to ensure that the asymptotic behavior of looking up a commit in an incremental chain is not dominated by the number of incrementals in that chain. It can be controlled by the '--max-commits' and '--size-multiple' options. In the next two commits, we will introduce additional splitting strategies that can exert additional control over: - when a split commit-graph is and isn't written, and - when the existing commit-graph chain is discarded completely and replaced with another graph To prepare for this, make '--split' take an optional strategy (as in '--split[=]'), and add a new enum to describe which strategy is being used. For now, no strategies are given, and the only enumerated value is 'COMMIT_GRAPH_SPLIT_UNSPECIFIED', indicating the absence of a strategy. Signed-off-by: Taylor Blau --- Documentation/git-commit-graph.txt | 11 ++++++----- builtin/commit-graph.c | 26 ++++++++++++++++++++++---- commit-graph.h | 5 +++++ 3 files changed, 33 insertions(+), 9 deletions(-) diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt index 28d1fee505..10d757c5cc 100644 --- a/Documentation/git-commit-graph.txt +++ b/Documentation/git-commit-graph.txt @@ -57,11 +57,12 @@ or `--stdin-packs`.) With the `--append` option, include all commits that are present in the existing commit-graph file. + -With the `--split` option, write the commit-graph as a chain of multiple -commit-graph files stored in `/info/commit-graphs`. The new commits -not already in the commit-graph are added in a new "tip" file. This file -is merged with the existing file if the following merge conditions are -met: +With the `--split[=]` option, write the commit-graph as a +chain of multiple commit-graph files stored in +`/info/commit-graphs`. Commit-graph layers are merged based on the +strategy and other splitting options. The new commits not already in the +commit-graph are added in a new "tip" file. This file is merged with the +existing file if the following merge conditions are met: + * If `--size-multiple=` is not specified, let `X` equal 2. If the new tip file would have `N` commits and the previous tip has `M` commits and diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c index d1ab6625f6..342094fc77 100644 --- a/builtin/commit-graph.c +++ b/builtin/commit-graph.c @@ -9,7 +9,9 @@ static char const * const builtin_commit_graph_usage[] = { N_("git commit-graph verify [--object-dir ] [--shallow] [--[no-]progress]"), - N_("git commit-graph write [--object-dir ] [--append|--split] [--reachable|--stdin-packs|--stdin-commits] [--[no-]progress] "), + N_("git commit-graph write [--object-dir ] [--append] " + "[--split[=]] [--reachable|--stdin-packs|--stdin-commits] " + "[--[no-]progress] "), NULL }; @@ -19,7 +21,9 @@ static const char * const builtin_commit_graph_verify_usage[] = { }; static const char * const builtin_commit_graph_write_usage[] = { - N_("git commit-graph write [--object-dir ] [--append|--split] [--reachable|--stdin-packs|--stdin-commits] [--[no-]progress] "), + N_("git commit-graph write [--object-dir ] [--append] " + "[--split[=]] [--reachable|--stdin-packs|--stdin-commits] " + "[--[no-]progress] "), NULL }; @@ -114,6 +118,18 @@ static int graph_verify(int argc, const char **argv) extern int read_replace_refs; static struct split_commit_graph_opts split_opts; +static int write_option_parse_split(const struct option *opt, const char *arg, + int unset) +{ + opts.split = 1; + if (!arg) + return 0; + + die(_("unrecognized --split argument, %s"), arg); + + return 0; +} + static int graph_write(int argc, const char **argv) { struct string_list *pack_indexes = NULL; @@ -136,8 +152,10 @@ static int graph_write(int argc, const char **argv) OPT_BOOL(0, "append", &opts.append, N_("include all commits already in the commit-graph file")), OPT_BOOL(0, "progress", &opts.progress, N_("force progress reporting")), - OPT_BOOL(0, "split", &opts.split, - N_("allow writing an incremental commit-graph file")), + OPT_CALLBACK_F(0, "split", &split_opts.flags, NULL, + N_("allow writing an incremental commit-graph file"), + PARSE_OPT_OPTARG | PARSE_OPT_NONEG, + write_option_parse_split), OPT_INTEGER(0, "max-commits", &split_opts.max_commits, N_("maximum number of commits in a non-base split commit-graph")), OPT_INTEGER(0, "size-multiple", &split_opts.size_multiple, diff --git a/commit-graph.h b/commit-graph.h index e87a6f6360..e799008ff4 100644 --- a/commit-graph.h +++ b/commit-graph.h @@ -82,10 +82,15 @@ enum commit_graph_write_flags { COMMIT_GRAPH_WRITE_CHECK_OIDS = (1 << 3) }; +enum commit_graph_split_flags { + COMMIT_GRAPH_SPLIT_UNSPECIFIED = 0 +}; + struct split_commit_graph_opts { int size_multiple; int max_commits; timestamp_t expire_time; + enum commit_graph_split_flags flags; }; /*