From b200d3ec2393a77476045e1e6739eef93b9201b6 Mon Sep 17 00:00:00 2001 From: Lessley Dennington Date: Fri, 17 Sep 2021 10:45:27 -0700 Subject: [PATCH] blame: enable and test the sparse index Enable the sparse index for the 'git blame' command. The index was already not expanded with this command, so the most interesting thing to do is to add tests that verify that 'git blame' behaves correctly when the sparse index is enabled and that its performance improves. More specifically, these cases are: 1. The index is not expanded for `blame` when given paths in the sparse checkout cone at multiple levels. 2. Performance measurably improves for `blame` with sparse index when given paths in the sparse checkout cone at multiple levels. The following are the performance results comparing the branch with sparse index enabled for `blame` with the vfs-2.33.0 branch in the microsoft/git repository: ``` Test msft/vfs-2.33.0 sparse-index-blame ----------------------------------------------------------------------------------- 2000.62: git blame f2/f4/a (full-v3) 0.31(0.21+0.09) 0.32(0.21+0.10) +3.2% 2000.63: git blame f2/f4/a (full-v4) 0.29(0.19+0.08) 0.31(0.21+0.08) +6.9% 2000.64: git blame f2/f4/a (sparse-v3) 0.55(0.38+0.14) 0.23(0.14+0.07) -58.2% 2000.65: git blame f2/f4/a (sparse-v4) 0.57(0.40+0.16) 0.23(0.15+0.07) -59.6% 2000.66: git blame f2/f4/f3/a (full-v3) 0.77(0.56+0.20) 0.85(0.60+0.22) +10.4% 2000.67: git blame f2/f4/f3/a (full-v4) 0.78(0.56+0.20) 0.81(0.59+0.21) +3.8% 2000.68: git blame f2/f4/f3/a (sparse-v3) 1.07(0.78+0.28) 0.72(0.52+0.19) -32.7% 2000.99: git blame f2/f4/f3/a (sparse-v4) 1.05(0.78+0.26) 0.73(0.51+0.19) -30.5% ``` We do not include paths outside the sparse checkout cone because blame currently does not support blaming files outside of the sparse definition. Attempting to do so fails with the following error: fatal: no such path '' in HEAD Signed-off-by: Lessley Dennington --- builtin/blame.c | 2 ++ t/perf/p2000-sparse-operations.sh | 2 ++ t/t1092-sparse-checkout-compatibility.sh | 9 +++++++++ 3 files changed, 13 insertions(+) diff --git a/builtin/blame.c b/builtin/blame.c index 7fafeac408141b..bda314c1658537 100644 --- a/builtin/blame.c +++ b/builtin/blame.c @@ -898,6 +898,8 @@ int cmd_blame(int argc, const char **argv, const char *prefix) long anchor; const int hexsz = the_hash_algo->hexsz; + prepare_repo_settings(the_repository); + the_repository->settings.command_requires_full_index = 0; setup_default_color_by_age(); git_config(git_blame_config, &output_option); repo_init_revisions(the_repository, &revs, NULL); diff --git a/t/perf/p2000-sparse-operations.sh b/t/perf/p2000-sparse-operations.sh index 1fdaa28f9b8039..aabcca8e26f285 100755 --- a/t/perf/p2000-sparse-operations.sh +++ b/t/perf/p2000-sparse-operations.sh @@ -124,5 +124,7 @@ test_perf_on_all git blame $SPARSE_CONE/a test_perf_on_all git blame $SPARSE_CONE/f3/a test_perf_on_all git update-index --add --remove test_perf_on_all git sparse-checkout reapply +test_perf_on_all git blame $SPARSE_CONE/a +test_perf_on_all git blame $SPARSE_CONE/f3/a test_done diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh index 1afab658f3d980..496e7f04b81919 100755 --- a/t/t1092-sparse-checkout-compatibility.sh +++ b/t/t1092-sparse-checkout-compatibility.sh @@ -1578,6 +1578,15 @@ test_expect_success 'stash -u outside sparse checkout definition' ' test_all_match git status --porcelain=v2 ' +test_expect_success 'sparse index is not expanded: blame' ' + init_repos && + + ensure_not_expanded blame a && + ensure_not_expanded blame deep/a && + ensure_not_expanded blame deep/deeper1/a && + ensure_not_expanded blame deep/deeper1/deepest/a +' + # NEEDSWORK: a sparse-checkout behaves differently from a full checkout # in this scenario, but it shouldn't. test_expect_success 'reset mixed and checkout orphan' '