Problem with wp_redirect(); function

The Plugin doesn’t work with the wp_redirect() function Code Reference.
I’ve create a function to redirect to subpage:

add_action( 'template_redirect', 'redirect_to_subpage');
  function redirect_to_subpage() {   
    global $post;
    $pagekids = get_pages("child_of=".$post->ID."&sort_column=menu_order");
    $emptycontent = get_post_field('post_content', $post->ID);	
    if ($pagekids && !$emptycontent) {
      $firstchild = $pagekids[0];
      return wp_redirect(get_permalink($firstchild->ID));
      exit;
    }
  }

When the Cache plugin are enabled the redirection doesn’t work.