Integrate `git-grep` with sparse-index and test the performance improvement. Changes since v1 ---------------- * Rewrite the commit message for "builtin/grep.c: add --sparse option" to be clearer. * Update the documentation (both in-code and man page) for --sparse. * Add a few tests to test the new behavior (when _only_ --cached is supplied). * Reformat the perf test results to not look like directly from p2000 tests. * Put the "command_requires_full_index" lines right after parse_options(). * Add a pathspec test in t1092, and reword a few test documentations. left-over-bits -------------- As Derrick suggested here [1], we can use tree traversing, for example `grep_tree()` in "builtin/grep.c", to grep each sparse directory, rather than expand the index directly, so we save some overheads. However, when testing "specifying a pathspec to limit the scope of tree walking", my local branch Git does not show the contents within the pathspec because of pathspec mismatch (which is not expected, when "folder1/*" is used, "folder1/a" failed to match?!). And when the pathspec is not used, Git walks all the trees as expected, because `all_entries_interesting` is returned for the empty pathspec. So I'm convinced that something is wrong with the pathspec matching logic within "builtin/grep.c", and I'm still working on it [2]. [1] https://lore.kernel.org/git/19dea639-389a-7258-e424-4912bde226df@xxxxxxxxxx/ [2] https://github.com/ffyuanda/git/tree/grep/sparse-integration-v2.3-tree-walking Shaoxuan Yuan (2): builtin/grep.c: add --sparse option builtin/grep.c: integrate with sparse index Documentation/git-grep.txt | 5 +++- builtin/grep.c | 20 +++++++++++--- t/perf/p2000-sparse-operations.sh | 1 + t/t1092-sparse-checkout-compatibility.sh | 18 +++++++++++++ t/t7817-grep-sparse-checkout.sh | 34 +++++++++++++++++++----- 5 files changed, 68 insertions(+), 10 deletions(-) Range-diff against v1: 1: bcac4dfc56 ! 1: 27c9341bca builtin/grep.c: add --sparse option @@ Metadata ## Commit message ## builtin/grep.c: add --sparse option - Add a --sparse option to `git-grep`. This option is mainly used to: + Add a --sparse option to `git-grep`. - If searching in the index (using --cached): + When the '--cached' option is used with the 'git grep' command, the + search is limited to the blobs found in the index, not in the worktree. + If the user has enabled sparse-checkout, this might present more results + than they would like, since the files outside of the sparse-checkout are + unlikely to be important to them. - With --sparse, proceed the action when the current cache_entry is - marked with SKIP_WORKTREE bit (the default is to skip this kind of - entry). Before this patch, --cached itself can realize this action. - Adding --sparse here grants the user finer control over sparse - entries. If the user only wants to peak into the index without - caring about sparse entries, --cached should suffice; if the user - wants to peak into the index _and_ cares about sparse entries, - combining --sparse with --cached can address this need. + Change the default behavior of 'git grep' to focus on the files within + the sparse-checkout definition. To enable the previous behavior, add a + '--sparse' option to 'git grep' that triggers the old behavior that + inspects paths outside of the sparse-checkout definition when paired + with the '--cached' option. + Helped-by: Derrick Stolee <derrickstolee@xxxxxxxxxx> Suggested-by: Victoria Dye <vdye@xxxxxxxxxx> Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@xxxxxxxxx> + ## Documentation/git-grep.txt ## +@@ Documentation/git-grep.txt: SYNOPSIS + [-f <file>] [-e] <pattern> + [--and|--or|--not|(|)|-e <pattern>...] + [--recurse-submodules] [--parent-basename <basename>] +- [ [--[no-]exclude-standard] [--cached | --no-index | --untracked] | <tree>...] ++ [ [--[no-]exclude-standard] [--cached [--sparse] | --no-index | --untracked] | <tree>...] + [--] [<pathspec>...] + + DESCRIPTION +@@ Documentation/git-grep.txt: OPTIONS + Instead of searching tracked files in the working tree, search + blobs registered in the index file. + ++--sparse:: ++ Use with --cached. Search outside of sparse-checkout definition. ++ + --no-index:: + Search files in the current directory that is not managed by Git. + + ## builtin/grep.c ## @@ builtin/grep.c: static pthread_cond_t cond_result; @@ builtin/grep.c: static int grep_cache(struct grep_opt *opt, - if (!cached && ce_skip_worktree(ce)) + /* -+ * If ce is a SKIP_WORKTREE entry, look into it when both -+ * --sparse and --cached are given. ++ * Skip entries with SKIP_WORKTREE unless both --sparse and ++ * --cached are given. + */ + if (!(grep_sparse && cached) && ce_skip_worktree(ce)) continue; @@ builtin/grep.c: int cmd_grep(int argc, const char **argv, const char *prefix) OPT_INTEGER('m', "max-count", &opt.max_count, N_("maximum number of results per file")), + OPT_BOOL(0, "sparse", &grep_sparse, -+ N_("search sparse contents and expand sparse index")), ++ N_("search the contents of files outside the sparse-checkout definition")), OPT_END() }; grep_prefix = prefix; @@ t/t7817-grep-sparse-checkout.sh: test_expect_success 'grep searches unmerged fil -test_expect_success 'grep --cached searches entries with the SKIP_WORKTREE bit' ' +test_expect_success 'grep --cached and --sparse searches entries with the SKIP_WORKTREE bit' ' ++ cat >expect <<-EOF && ++ a:text ++ EOF ++ git grep --cached "text" >actual && ++ test_cmp expect actual && ++ cat >expect <<-EOF && a:text b:text @@ t/t7817-grep-sparse-checkout.sh: test_expect_success 'grep --recurse-submodules -test_expect_success 'grep --recurse-submodules --cached searches entries with the SKIP_WORKTREE bit' ' +test_expect_success 'grep --recurse-submodules --cached and --sparse searches entries with the SKIP_WORKTREE bit' ' ++ cat >expect <<-EOF && ++ a:text ++ sub/B/b:text ++ sub2/a:text ++ EOF ++ git grep --recurse-submodules --cached "text" >actual && ++ test_cmp expect actual && ++ cat >expect <<-EOF && a:text b:text @@ t/t7817-grep-sparse-checkout.sh: test_expect_success 'working tree grep does not -test_expect_success 'grep --cached searches index entries with both CE_VALID and SKIP_WORKTREE' ' +test_expect_success 'grep --cached and --sparse searches index entries with both CE_VALID and SKIP_WORKTREE' ' ++ cat >expect <<-EOF && ++ a:text ++ EOF ++ test_when_finished "git update-index --no-assume-unchanged b" && ++ git update-index --assume-unchanged b && ++ git grep --cached text >actual && ++ test_cmp expect actual && ++ cat >expect <<-EOF && a:text b:text 2: 48b21afb94 ! 2: cb16727c05 builtin/grep.c: integrate with sparse index @@ Commit message The p2000 tests demonstrate a ~99.4% execution time reduction for `git grep` using a sparse index. - Test HEAD~1 HEAD + Test Before After ----------------------------------------------------------------------------- - 2000.78: git grep --cached bogus (full-v3) 0.019 0.018 (-5.2%) - 2000.79: git grep --cached bogus (full-v4) 0.017 0.016 (-5.8%) - 2000.80: git grep --cached bogus (sparse-v3) 0.29 0.0015 (-99.4%) - 2000.81: git grep --cached bogus (sparse-v4) 0.30 0.0018 (-99.4%) + git grep --cached bogus (full-v3) 0.019 0.018 (-5.2%) + git grep --cached bogus (full-v4) 0.017 0.016 (-5.8%) + git grep --cached bogus (sparse-v3) 0.29 0.0015 (-99.4%) + git grep --cached bogus (sparse-v4) 0.30 0.0018 (-99.4%) Optional reading about performance test results ----------------------------------------------- @@ Commit message ## builtin/grep.c ## @@ builtin/grep.c: static int grep_cache(struct grep_opt *opt, - strbuf_addstr(&name, repo->submodule_prefix); - } - -+ prepare_repo_settings(repo); -+ repo->settings.command_requires_full_index = 0; -+ if (repo_read_index(repo) < 0) die(_("index file corrupt")); @@ builtin/grep.c: static int grep_cache(struct grep_opt *opt, for (nr = 0; nr < repo->index->cache_nr; nr++) { const struct cache_entry *ce = repo->index->cache[nr]; +@@ builtin/grep.c: int cmd_grep(int argc, const char **argv, const char *prefix) + PARSE_OPT_KEEP_DASHDASH | + PARSE_OPT_STOP_AT_NON_OPTION); + ++ if (the_repository->gitdir) { ++ prepare_repo_settings(the_repository); ++ the_repository->settings.command_requires_full_index = 0; ++ } ++ + if (use_index && !startup_info->have_repository) { + int fallback = 0; + git_config_get_bool("grep.fallbacktonoindex", &fallback); ## t/perf/p2000-sparse-operations.sh ## @@ t/perf/p2000-sparse-operations.sh: test_perf_on_all git read-tree -mu HEAD @@ t/t1092-sparse-checkout-compatibility.sh: test_expect_success 'sparse index is n ensure_not_expanded rm -r deep ' -+test_expect_success 'grep expands index using --sparse' ' ++test_expect_success 'grep with --sparse and --cached' ' + init_repos && + -+ # With --sparse and --cached, do not ignore sparse entries and -+ # expand the index. -+ test_all_match git grep --sparse --cached a ++ test_all_match git grep --sparse --cached a && ++ test_all_match git grep --sparse --cached a -- "folder1/*" +' + +test_expect_success 'grep is not expanded' ' @@ t/t1092-sparse-checkout-compatibility.sh: test_expect_success 'sparse index is n + + ensure_not_expanded grep a && + ensure_not_expanded grep a -- deep/* && -+ # grep does not match anything per se, so ! is used ++ ++ # All files within the folder1/* pathspec are sparse, ++ # so this command does not find any matches + ensure_not_expanded ! grep a -- folder1/* +' + base-commit: 07ee72db0e97b5c233f8ada0abb412248c2f1c6f -- 2.37.0
