diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index e5b0119a5c..7dad3c1064 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -152,13 +152,6 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
   protected $classLoader;
 
   /**
-   * The class loader class before including settings.php.
-   *
-   * @var string
-   */
-  protected $preSettingsClassLoaderClass;
-
-  /**
    * Config storage object used for reading enabled modules configuration.
    *
    * @var \Drupal\Core\Config\StorageInterface
@@ -897,34 +890,6 @@ protected function initializeContainer() {
       $container = new $class($container_definition);
     }
 
-    // If the class loader is still the same as before including settings.php
-    // use an optimised classloader if possible.
-    if ($this->preSettingsClassLoaderClass == get_class($this->classLoader)
-      && Settings::get('class_loader_auto_detect', TRUE)) {
-      $prefix = Settings::getApcuPrefix('class_loader', $this->root);
-      // We have to key by module list since if this changes the classloader
-      // might have negative caches for classes that now exist.
-      $prefix .= '.' . hash('sha1', serialize(array_keys($container->getParameter('container.modules'))));
-      $loader = NULL;
-
-      // We autodetect one of the following three optimized classloaders, if
-      // their underlying extension exists.
-      if (function_exists('apcu_fetch')) {
-        $loader = new ApcClassLoader($prefix, $this->classLoader);
-      }
-      elseif (extension_loaded('wincache')) {
-        $loader = new WinCacheClassLoader($prefix, $this->classLoader);
-      }
-      elseif (extension_loaded('xcache')) {
-        $loader = new XcacheClassLoader($prefix, $this->classLoader);
-      }
-      if (!empty($loader)) {
-        $this->classLoader->unregister();
-        $loader->register();
-        $this->classLoader = $loader;
-      }
-    }
-
     $this->attachSynthetic($container);
 
     $this->container = $container;
@@ -1053,7 +1018,7 @@ public static function bootEnvironment($app_root = NULL) {
   protected function initializeSettings(Request $request) {
     $site_path = static::findSitePath($request);
     $this->setSitePath($site_path);
-    $this->preSettingsClassLoaderClass = get_class($this->classLoader);
+    $class_loader_class = get_class($this->classLoader);
     Settings::initialize($this->root, $site_path, $this->classLoader);
 
     // Initialize our list of trusted HTTP Host headers to protect against
@@ -1067,7 +1032,7 @@ protected function initializeSettings(Request $request) {
 
     // If the class loader is still the same, possibly
     // upgrade to an optimized class loader.
-    if ($this->preSettingsClassLoaderClass == get_class($this->classLoader)
+    if ($class_loader_class == get_class($this->classLoader)
         && Settings::get('class_loader_auto_detect', TRUE)) {
       $prefix = Settings::getApcuPrefix('class_loader', $this->root);
       $loader = NULL;