commit fd77650a2d2970938d0c48d320258aa8e497e024
from: Stefan Sperling <stsp@stsp.name>
via: Thomas Adam <thomas@xteddy.org>
date: Tue Mar 19 13:37:06 2024 UTC

speed up got tag -l by caching timestamps in got_ref_cmp_tags() 

performance problem reported by naddy@

commit - ab0b42add3dde1ffda7a71bc6da7c87aabf70311
commit + fd77650a2d2970938d0c48d320258aa8e497e024
blob - 2861fcb92918d1fb25573f0745ee98c008a4b0c9
blob + 0eccf9a0d4a076a217aaada72bc6bf41f3a186f2
--- lib/reference.c
+++ lib/reference.c
@@ -88,7 +88,10 @@ struct got_reference {
 	struct got_lockfile *lf;
 	time_t mtime;
 
-	/* Cached timestamp for got_ref_cmp_by_commit_timestamp_descending() */
+	/*
+	 * Cached timestamp for got_ref_cmp_by_commit_timestamp_descending()
+	 * and got_ref_cmp_tags().
+	 */
 	time_t committer_time;
 };
 
@@ -647,70 +650,6 @@ got_ref_cmp_by_name(void *arg, int *cmp, struct got_re
 
 	*cmp = got_path_cmp(name1, name2, strlen(name1), strlen(name2));
 	return NULL;
-}
-
-const struct got_error *
-got_ref_cmp_tags(void *arg, int *cmp, struct got_reference *ref1,
-    struct got_reference *ref2)
-{
-	const struct got_error *err = NULL;
-	struct got_repository *repo = arg;
-	struct got_object_id *id1, *id2 = NULL;
-	struct got_tag_object *tag1 = NULL, *tag2 = NULL;
-	struct got_commit_object *commit1 = NULL, *commit2 = NULL;
-	time_t time1, time2;
-
-	*cmp = 0;
-
-	err = got_ref_resolve(&id1, repo, ref1);
-	if (err)
-		return err;
-	err = got_object_open_as_tag(&tag1, repo, id1);
-	if (err) {
-		if (err->code != GOT_ERR_OBJ_TYPE)
-			goto done;
-		/* "lightweight" tag */
-		err = got_object_open_as_commit(&commit1, repo, id1);
-		if (err)
-			goto done;
-		time1 = got_object_commit_get_committer_time(commit1);
-	} else
-		time1 = got_object_tag_get_tagger_time(tag1);
-
-	err = got_ref_resolve(&id2, repo, ref2);
-	if (err)
-		goto done;
-	err = got_object_open_as_tag(&tag2, repo, id2);
-	if (err) {
-		if (err->code != GOT_ERR_OBJ_TYPE)
-			goto done;
-		/* "lightweight" tag */
-		err = got_object_open_as_commit(&commit2, repo, id2);
-		if (err)
-			goto done;
-		time2 = got_object_commit_get_committer_time(commit2);
-	} else
-		time2 = got_object_tag_get_tagger_time(tag2);
-
-	/* Put latest tags first. */
-	if (time1 < time2)
-		*cmp = 1;
-	else if (time1 > time2)
-		*cmp = -1;
-	else
-		err = got_ref_cmp_by_name(NULL, cmp, ref2, ref1);
-done:
-	free(id1);
-	free(id2);
-	if (tag1)
-		got_object_tag_close(tag1);
-	if (tag2)
-		got_object_tag_close(tag2);
-	if (commit1)
-		got_object_commit_close(commit1);
-	if (commit2)
-		got_object_commit_close(commit2);
-	return err;
 }
 
 static const struct got_error *
@@ -759,6 +698,37 @@ done:
 }
 
 const struct got_error *
+got_ref_cmp_tags(void *arg, int *cmp, struct got_reference *ref1,
+    struct got_reference *ref2)
+{
+	const struct got_error *err = NULL;
+	struct got_repository *repo = arg;
+
+	*cmp = 0;
+
+	if (ref1->committer_time == 0) {
+		err = get_committer_time(ref1, repo);
+		if (err)
+			return err;
+	}
+	if (ref2->committer_time == 0) {
+		err = get_committer_time(ref2, repo);
+		if (err)
+			return err;
+	}
+
+	/* Put latest tags first. */
+	if (ref1->committer_time < ref2->committer_time)
+		*cmp = 1;
+	else if (ref1->committer_time > ref2->committer_time)
+		*cmp = -1;
+	else
+		err = got_ref_cmp_by_name(NULL, cmp, ref2, ref1);
+
+	return err;
+}
+
+const struct got_error *
 got_ref_cmp_by_commit_timestamp_descending(void *arg, int *cmp,
     struct got_reference *ref1, struct got_reference *ref2)
 {