diff --git a/src/encoding/xml/marshal_test.go b/src/encoding/xml/marshal_test.go
index 4fb901f258..674c6b5b3f 100644
--- a/src/encoding/xml/marshal_test.go
+++ b/src/encoding/xml/marshal_test.go
@@ -1901,17 +1901,21 @@ func TestMarshalFlush(t *testing.T) {
 
 func BenchmarkMarshal(b *testing.B) {
 	b.ReportAllocs()
-	for i := 0; i < b.N; i++ {
-		Marshal(atomValue)
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			Marshal(atomValue)
+		}
+	})
 }
 
 func BenchmarkUnmarshal(b *testing.B) {
 	b.ReportAllocs()
 	xml := []byte(atomXml)
-	for i := 0; i < b.N; i++ {
-		Unmarshal(xml, &Feed{})
-	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			Unmarshal(xml, &Feed{})
+		}
+	})
 }
 
 // golang.org/issue/6556