From patchwork Wed Jul 1 13:27:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Schindelin via GitGitGadget X-Patchwork-Id: 11636387 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 8658B13B4 for ; Wed, 1 Jul 2020 13:27:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 698A1207F9 for ; Wed, 1 Jul 2020 13:27:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IJBa8TFE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731094AbgGAN1l (ORCPT ); Wed, 1 Jul 2020 09:27:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730729AbgGAN1h (ORCPT ); Wed, 1 Jul 2020 09:27:37 -0400 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3F2EC08C5DB for ; Wed, 1 Jul 2020 06:27:36 -0700 (PDT) Received: by mail-wm1-x342.google.com with SMTP id f139so23242925wmf.5 for ; Wed, 01 Jul 2020 06:27:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=IQiadWATS38fXopJv59PiR9qTXIDXVfzvd4sBRhCSSg=; b=IJBa8TFEZQfm2xQTzWXVf8+kgiXSqOIqIMTchm1nLif+AgvTOqODbVlibv5doKeEdU x4EVaQE9BUHZW2/aJ03/9UJjoy4crP0PNx2k5oE+UdSGjZ7wjbr34Qz+jItTShK/106B sajvqlK3V0+LOMPck/Tjeb3zmRHNbqgQbFYh5wK3Y6f3YUXsuMEsvKxZHKCQyaggIfk0 blyTRtIjpNps7KwQ7/oODQfBpGZ0A7zj5IHEmdD7eRZ/NCoJYucO+aiwdMZfs0K/sc+c JK8mnzKyEi+8SWBN0aK7gyavGHN5kLKhutjV+hyUOfXCiT0HiH1H1UQ9DoUGHIFeDuUn F8OA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=IQiadWATS38fXopJv59PiR9qTXIDXVfzvd4sBRhCSSg=; b=HPeiGWHDTZ9ihKvICyHPDVkfpqrsRAsfugBfrw5D1IZDp3pdl4v73uDrMQod0GDY2G hwdgoyvRFZPlfuCmqxvFlxU54iQP9wj7d5U3CYXc5OF52OwcBZufYa7b3p7jVbx+kT21 K3JmH16MI/WxxqmT4Lfvuo1juwCjt3FRl8izX3A86X+hAa00Z3nE6XmLaPKvpZQZiuYs 2xJ60dH1qh0/7bIjtJNmUO3MOiCmIhzvdstj+rYyJmhzeTilRA/1er06H3jyVA59Vc7o s2KG4AfpdNrqFAMOLaEQiwn1Yj5qTYEBkNJdUVOMv2EWhiKGXoIg+5iZAyd1WQ9HF7Pu P1Cw== X-Gm-Message-State: AOAM533PVV2IIOMsIyhFTWrtGBzhENLlk5iWjayCEpTMRZzriJeQ3oFD 1f9Innjwgcp0q6kIc63Z0qYq/TuV X-Google-Smtp-Source: ABdhPJyBOOhBRkQZEqoSxIcozTm8NsZGt8mTw/PQOLQkwjL0KYKSVwvz2UVgQQmcIXrOMj0l7dGeCQ== X-Received: by 2002:a1c:7d56:: with SMTP id y83mr25784668wmc.154.1593610055292; Wed, 01 Jul 2020 06:27:35 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id h13sm7382194wml.42.2020.07.01.06.27.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Jul 2020 06:27:34 -0700 (PDT) Message-Id: In-Reply-To: References: From: "Derrick Stolee via GitGitGadget" Date: Wed, 01 Jul 2020 13:27:24 +0000 Subject: [PATCH v4 04/10] commit-graph: persist existence of changed-paths Fcc: Sent MIME-Version: 1.0 To: git@vger.kernel.org Cc: me@ttaylorr.com, szeder.dev@gmail.com, l.s.r@web.de, Derrick Stolee , Derrick Stolee Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Derrick Stolee The changed-path Bloom filters were released in v2.27.0, but have a significant drawback. A user can opt-in to writing the changed-path filters using the "--changed-paths" option to "git commit-graph write" but the next write will drop the filters unless that option is specified. This becomes even more important when considering the interaction with gc.writeCommitGraph (on by default) or fetch.writeCommitGraph (part of features.experimental). These config options trigger commit-graph writes that the user did not signal, and hence there is no --changed-paths option available. Allow a user that opts-in to the changed-path filters to persist the property of "my commit-graph has changed-path filters" automatically. A user can drop filters using the --no-changed-paths option. In the process, we need to be extremely careful to match the Bloom filter settings as specified by the commit-graph. This will allow future versions of Git to customize these settings, and the version with this change will persist those settings as commit-graphs are rewritten on top. Use the trace2 API to signal the settings used during the write, and check that output in a test after manually adjusting the correct bytes in the commit-graph file. Signed-off-by: Derrick Stolee --- Documentation/git-commit-graph.txt | 5 +++- builtin/commit-graph.c | 5 +++- commit-graph.c | 45 ++++++++++++++++++++++++++++-- commit-graph.h | 1 + t/t4216-log-bloom.sh | 17 ++++++++++- 5 files changed, 67 insertions(+), 6 deletions(-) diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt index f4b13c005b..369b222b08 100644 --- a/Documentation/git-commit-graph.txt +++ b/Documentation/git-commit-graph.txt @@ -60,7 +60,10 @@ existing commit-graph file. With the `--changed-paths` option, compute and write information about the paths changed between a commit and it's first parent. This operation can take a while on large repositories. It provides significant performance gains -for getting history of a directory or a file with `git log -- `. +for getting history of a directory or a file with `git log -- `. If +this option is given, future commit-graph writes will automatically assume +that this option was intended. Use `--no-changed-paths` to stop storing this +data. + With the `--split` option, write the commit-graph as a chain of multiple commit-graph files stored in `/info/commit-graphs`. The new commits diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c index 59009837dc..ff7b177c33 100644 --- a/builtin/commit-graph.c +++ b/builtin/commit-graph.c @@ -151,6 +151,7 @@ static int graph_write(int argc, const char **argv) }; opts.progress = isatty(2); + opts.enable_changed_paths = -1; split_opts.size_multiple = 2; split_opts.max_commits = 0; split_opts.expire_time = 0; @@ -171,7 +172,9 @@ static int graph_write(int argc, const char **argv) flags |= COMMIT_GRAPH_WRITE_SPLIT; if (opts.progress) flags |= COMMIT_GRAPH_WRITE_PROGRESS; - if (opts.enable_changed_paths || + if (!opts.enable_changed_paths) + flags |= COMMIT_GRAPH_NO_WRITE_BLOOM_FILTERS; + if (opts.enable_changed_paths == 1 || git_env_bool(GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS, 0)) flags |= COMMIT_GRAPH_WRITE_BLOOM_FILTERS; diff --git a/commit-graph.c b/commit-graph.c index 50ce039a53..6762704324 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -16,6 +16,8 @@ #include "progress.h" #include "bloom.h" #include "commit-slab.h" +#include "json-writer.h" +#include "trace2.h" void git_test_write_commit_graph_or_die(void) { @@ -1108,6 +1110,21 @@ static void write_graph_chunk_bloom_indexes(struct hashfile *f, stop_progress(&progress); } +static void trace2_bloom_filter_settings(struct write_commit_graph_context *ctx) +{ + struct json_writer jw = JSON_WRITER_INIT; + + jw_object_begin(&jw, 0); + jw_object_intmax(&jw, "hash_version", ctx->bloom_settings->hash_version); + jw_object_intmax(&jw, "num_hashes", ctx->bloom_settings->num_hashes); + jw_object_intmax(&jw, "bits_per_entry", ctx->bloom_settings->bits_per_entry); + jw_end(&jw); + + trace2_data_json("bloom", ctx->r, "settings", &jw); + + jw_release(&jw); +} + static void write_graph_chunk_bloom_data(struct hashfile *f, struct write_commit_graph_context *ctx) { @@ -1116,6 +1133,8 @@ static void write_graph_chunk_bloom_data(struct hashfile *f, struct progress *progress = NULL; int i = 0; + trace2_bloom_filter_settings(ctx); + if (ctx->report_progress) progress = start_delayed_progress( _("Writing changed paths Bloom filters data"), @@ -1547,9 +1566,15 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx) int num_chunks = 3; uint64_t chunk_offset; struct object_id file_hash; - const struct bloom_filter_settings bloom_settings = DEFAULT_BLOOM_FILTER_SETTINGS; + struct bloom_filter_settings bloom_settings = DEFAULT_BLOOM_FILTER_SETTINGS; - ctx->bloom_settings = &bloom_settings; + if (!ctx->bloom_settings) { + bloom_settings.bits_per_entry = git_env_ulong("GIT_TEST_BLOOM_SETTINGS_BITS_PER_ENTRY", + bloom_settings.bits_per_entry); + bloom_settings.num_hashes = git_env_ulong("GIT_TEST_BLOOM_SETTINGS_NUM_HASHES", + bloom_settings.num_hashes); + ctx->bloom_settings = &bloom_settings; + } if (ctx->split) { struct strbuf tmp_file = STRBUF_INIT; @@ -1974,9 +1999,23 @@ int write_commit_graph(struct object_directory *odb, ctx->split = flags & COMMIT_GRAPH_WRITE_SPLIT ? 1 : 0; ctx->check_oids = flags & COMMIT_GRAPH_WRITE_CHECK_OIDS ? 1 : 0; ctx->split_opts = split_opts; - ctx->changed_paths = flags & COMMIT_GRAPH_WRITE_BLOOM_FILTERS ? 1 : 0; ctx->total_bloom_filter_data_size = 0; + if (flags & COMMIT_GRAPH_WRITE_BLOOM_FILTERS) + ctx->changed_paths = 1; + if (!(flags & COMMIT_GRAPH_NO_WRITE_BLOOM_FILTERS)) { + struct commit_graph *g; + prepare_commit_graph_one(ctx->r, ctx->odb); + + g = ctx->r->objects->commit_graph; + + /* We have changed-paths already. Keep them in the next graph */ + if (g && g->chunk_bloom_data) { + ctx->changed_paths = 1; + ctx->bloom_settings = g->bloom_filter_settings; + } + } + if (ctx->split) { struct commit_graph *g; prepare_commit_graph(ctx->r); diff --git a/commit-graph.h b/commit-graph.h index f0fb13e3f2..45b1e5bca3 100644 --- a/commit-graph.h +++ b/commit-graph.h @@ -96,6 +96,7 @@ enum commit_graph_write_flags { /* Make sure that each OID in the input is a valid commit OID. */ COMMIT_GRAPH_WRITE_CHECK_OIDS = (1 << 3), COMMIT_GRAPH_WRITE_BLOOM_FILTERS = (1 << 4), + COMMIT_GRAPH_NO_WRITE_BLOOM_FILTERS = (1 << 5), }; struct split_commit_graph_opts { diff --git a/t/t4216-log-bloom.sh b/t/t4216-log-bloom.sh index 2761208e74..52ad998f9e 100755 --- a/t/t4216-log-bloom.sh +++ b/t/t4216-log-bloom.sh @@ -126,7 +126,7 @@ test_expect_success 'setup - add commit-graph to the chain without Bloom filters test_commit c14 A/anotherFile2 && test_commit c15 A/B/anotherFile2 && test_commit c16 A/B/C/anotherFile2 && - GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS=0 git commit-graph write --reachable --split && + git commit-graph write --reachable --split --no-changed-paths && test_line_count = 2 .git/objects/info/commit-graphs/commit-graph-chain ' @@ -152,6 +152,21 @@ test_expect_success 'Use Bloom filters if they exist in the latest but not all c test_bloom_filters_used_when_some_filters_are_missing "-- A/B" ' +test_expect_success 'persist filter settings' ' + test_when_finished rm -rf .git/objects/info/commit-graph* && + rm -rf .git/objects/info/commit-graph* && + GIT_TRACE2_EVENT="$(pwd)/trace2.txt" \ + GIT_TRACE2_EVENT_NESTING=5 \ + GIT_TEST_BLOOM_SETTINGS_NUM_HASHES=9 \ + GIT_TEST_BLOOM_SETTINGS_BITS_PER_ENTRY=15 \ + git commit-graph write --reachable --changed-paths && + grep "{\"hash_version\":1,\"num_hashes\":9,\"bits_per_entry\":15}" trace2.txt && + GIT_TRACE2_EVENT="$(pwd)/trace2-auto.txt" \ + GIT_TRACE2_EVENT_NESTING=5 \ + git commit-graph write --reachable --changed-paths && + grep "{\"hash_version\":1,\"num_hashes\":9,\"bits_per_entry\":15}" trace2-auto.txt +' + test_expect_success 'correctly report changes over limit' ' git init 513changes && (