diff --git a/t/perf/p0004-lazy-init-name-hash.sh b/t/perf/p0004-lazy-init-name-hash.sh
index 576bdc3c4e..d30c32f97b 100755
--- a/t/perf/p0004-lazy-init-name-hash.sh
+++ b/t/perf/p0004-lazy-init-name-hash.sh
@@ -18,4 +18,40 @@ test_expect_success 'multithreaded should be faster' '
 	test-lazy-init-name-hash --perf >out.perf
 '
 
+test_expect_success 'calibrate' '
+	entries=$(wc -l <out.single) &&
+
+	case $entries in
+	?) count=1000000 ;;
+	??) count=100000 ;;
+	???) count=10000 ;;
+	????) count=1000 ;;
+	?????) count=100 ;;
+	??????) count=10 ;;
+	*) count=1 ;;
+	esac &&
+	export count &&
+
+	case $entries in
+	1) entries_desc="1 entry" ;;
+	*) entries_desc="$entries entries" ;;
+	esac &&
+
+	case $count in
+	1) count_desc="1 round" ;;
+	*) count_desc="$count rounds" ;;
+	esac &&
+
+	desc="$entries_desc, $count_desc" &&
+	export desc
+'
+
+test_perf "single-threaded, $desc" "
+	test-lazy-init-name-hash --single --count=$count
+"
+
+test_perf "multi-threaded, $desc" "
+	test-lazy-init-name-hash --multi --count=$count
+"
+
 test_done