sparse-index: count lstat() calls
The clear_skip_worktree.. methods already report some statistics about how many cache entries are checked against path_found() due to having the skip-worktree bit set. However, due to path_found() performing some caching, this isn't the only information that would be helpful to report. Add a new lstat_count member to the path_found_data struct to count the number of times path_found() calls lstat(). This will be helpful to help explain performance problems in this method as well as to demonstrate future changes to the caching algorithm in a more concrete way than end-to-end timings. Signed-off-by: Derrick Stolee <stolee@gmail.com> Reviewed-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee committed
Jun 28, 2024 at 12:43 UTC
c4e8c42c19ecc354abacd97c61c808383c0870fa
1 file changed
+7
sparse-index.c
+7
@@ -442,6 +442,7 @@ void ensure_correct_sparsity(struct index_state *istate)
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struct path_found_data {
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struct strbuf dir;
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int dir_found;
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+ size_t lstat_count;
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};
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#define PATH_FOUND_DATA_INIT { \
@@ -469,6 +470,7 @@ static int path_found(const char *path, struct path_found_data *data)
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/*
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* If path itself exists, return 1.
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*/
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+ data->lstat_count++;
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if (!lstat(path, &st))
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return 1;
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@@ -493,6 +495,7 @@ static int path_found(const char *path, struct path_found_data *data)
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strbuf_reset(&data->dir);
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strbuf_add(&data->dir, path, newdir - path + 1);
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+ data->lstat_count++;
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data->dir_found = !lstat(data->dir.buf, &st);
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return 0;
@@ -524,6 +527,8 @@ static int clear_skip_worktree_from_present_files_sparse(struct index_state *ist
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trace2_data_intmax("index", istate->repo,
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"sparse_path_count", path_count);
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+ trace2_data_intmax("index", istate->repo,
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+ "sparse_lstat_count", data.lstat_count);
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trace2_region_leave("index", "clear_skip_worktree_from_present_files_sparse",
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istate->repo);
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clear_path_found_data(&data);
@@ -553,6 +558,8 @@ static void clear_skip_worktree_from_present_files_full(struct index_state *ista
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trace2_data_intmax("index", istate->repo,
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"full_path_count", path_count);
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+ trace2_data_intmax("index", istate->repo,
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+ "full_lstat_count", data.lstat_count);
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trace2_region_leave("index", "clear_skip_worktree_from_present_files_full",
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istate->repo);
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clear_path_found_data(&data);