diff -u b/core/modules/system/tests/modules/batch_test/batch_test.callbacks.inc b/core/modules/system/tests/modules/batch_test/batch_test.callbacks.inc
--- b/core/modules/system/tests/modules/batch_test/batch_test.callbacks.inc
+++ b/core/modules/system/tests/modules/batch_test/batch_test.callbacks.inc
@@ -106,9 +106,10 @@
   // Use item list template to render the messages.
   $error_message = [
     '#type' => 'inline_template',
-    '#template' => 'results for batch {{ batch_id }}{{ errors }}',
+    '#template' => 'results for batch {{ batch_id }} ({{ elapsed }}){{ errors }}',
     '#context' => [
       'batch_id' => $batch_id,
+      'elapsed' => $elapsed,
       'errors' => [
         '#theme' => 'item_list',
         '#items' => $messages,
@@ -117,6 +118,8 @@
   ];
 
   drupal_set_message(\Drupal::service('renderer')->renderPlain($error_message));
+
+  drupal_set_message('elapsed time: ' . $elapsed);
 }
 
 /**
only in patch2:
unchanged:
--- a/core/lib/Drupal/Core/Form/form.api.php
+++ b/core/lib/Drupal/Core/Form/form.api.php
@@ -109,12 +109,15 @@ function callback_batch_operation($multiple_params, &$context) {
  *   The value set in $context['results'] by callback_batch_operation().
  * @param $operations
  *   If $success is FALSE, contains the operations that remained unprocessed.
+ * @param $elapsed
+ *   A string which represents the elapsed time for the batch process.
  */
-function callback_batch_finished($success, $results, $operations) {
+function callback_batch_finished($success, $results, $operations, $elapsed) {
   if ($success) {
     // Here we do something meaningful with the results.
-    $message = t("@count items were processed.", [
+    $message = t("@count items were processed (@elapsed).", [
       '@count' => count($results),
+      '@elapsed' => $elapsed,
       ]);
     $list = [
       '#theme' => 'item_list',
only in patch2:
unchanged:
--- a/core/modules/system/tests/src/Functional/Batch/ProcessingTest.php
+++ b/core/modules/system/tests/src/Functional/Batch/ProcessingTest.php
@@ -265,30 +265,31 @@ public function _resultStack($id, $value = 0) {
   public function _resultMessages($id) {
     $messages = [];
 
+    $pattern_elapsed = ' \((\d+ min )?\d+ sec\)';
     switch ($id) {
       case 'batch_0':
-        $messages[] = 'results for batch 0<div class="item-list"><ul><li>none</li></ul></div>';
+        $messages[] = 'results for batch 0' . $pattern_elapsed . '<div class="item-list"><ul><li>none</li></ul></div>';
         break;
 
       case 'batch_1':
-        $messages[] = 'results for batch 1<div class="item-list"><ul><li>op 1: processed 10 elements</li></ul></div>';
+        $messages[] = 'results for batch 1' . $pattern_elapsed . '<div class="item-list"><ul><li>op 1: processed 10 elements</li></ul></div>';
         break;
 
       case 'batch_2':
-        $messages[] = 'results for batch 2<div class="item-list"><ul><li>op 2: processed 10 elements</li></ul></div>';
+        $messages[] = 'results for batch 2' . $pattern_elapsed . '<div class="item-list"><ul><li>op 2: processed 10 elements</li></ul></div>';
         break;
 
       case 'batch_3':
-        $messages[] = 'results for batch 3<div class="item-list"><ul><li>op 1: processed 10 elements</li><li>op 2: processed 10 elements</li></ul></div>';
+        $messages[] = 'results for batch 3' . $pattern_elapsed . '<div class="item-list"><ul><li>op 1: processed 10 elements</li><li>op 2: processed 10 elements</li></ul></div>';
         break;
 
       case 'batch_4':
-        $messages[] = 'results for batch 4<div class="item-list"><ul><li>op 1: processed 10 elements</li></ul></div>';
+        $messages[] = 'results for batch 4' . $pattern_elapsed . '<div class="item-list"><ul><li>op 1: processed 10 elements</li></ul></div>';
         $messages = array_merge($messages, $this->_resultMessages('batch_2'));
         break;
 
       case 'batch_5':
-        $messages[] = 'results for batch 5<div class="item-list"><ul><li>op 5: processed 10 elements</li></ul></div>';
+        $messages[] = 'results for batch 5' . $pattern_elapsed . '<div class="item-list"><ul><li>op 5: processed 10 elements</li></ul></div>';
         break;
 
       case 'chained':