diff --git a/core/includes/Drupal/Cache/CacheBackendInterface.php b/core/includes/Drupal/Cache/CacheBackendInterface.php
index 3cb3c46..546478b 100644
--- a/core/includes/Drupal/Cache/CacheBackendInterface.php
+++ b/core/includes/Drupal/Cache/CacheBackendInterface.php
@@ -11,21 +11,22 @@ namespace Drupal\Cache;
  * Defines an interface for cache implementations.
  *
  * All cache implementations have to implement this interface.
- * DrupalDatabaseCache provides the default implementation, which can be
- * consulted as an example.
+ * Drupal\Cache\DatabaseBackend provides the default implementation, which can
+ * be consulted as an example.
  *
  * To make Drupal use your implementation for a certain cache bin, you have to
  * set a variable with the name of the cache bin as its key and the name of
  * your class as its value. For example, if your implementation of
- * DrupalCacheInterface was called MyCustomCache, the following line would make
- * Drupal use it for the 'cache_page' bin:
+ * Drupal\Cache\CacheBackendInterface was called MyCustomCache, the following
+ * line would make Drupal use it for the 'cache_page' bin:
  * @code
  *  variable_set('cache_class_cache_page', 'MyCustomCache');
  * @endcode
  *
  * Additionally, you can register your cache implementation to be used by
  * default for all cache bins by setting the variable 'cache_default_class' to
- * the name of your implementation of the DrupalCacheInterface, e.g.
+ * the name of your implementation of the Drupal\Cache\CacheBackendInterface,
+ * e.g.
  * @code
  *  variable_set('cache_default_class', 'MyCustomCache');
  * @endcode
@@ -42,7 +43,7 @@ namespace Drupal\Cache;
  * @endcode
  *
  * @see cache()
- * @see DrupalDatabaseCache
+ * @see Drupal\Cache\DatabaseBackend
  */
 interface CacheBackendInterface {
 
diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index 3f5eb2e..a6594e1 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -277,7 +277,7 @@ function install_begin_request(&$install_state) {
   // because any data put in the cache during the installer is inherently
   // suspect, due to the fact that Drupal is not fully set up yet.
   require_once DRUPAL_ROOT . '/core/includes/cache.inc';
-  $conf['cache_default_class'] = 'Drupal\\Cache\\InstallBackend';
+  $conf['cache_default_class'] = 'Drupal\Cache\InstallBackend';
 
   // Prepare for themed output. We need to run this at the beginning of the
   // page request to avoid a different theme accidentally getting set. (We also
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 26591ab..f40606f 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -1471,7 +1471,7 @@ function system_schema() {
         'default' => 0,
       ),
       'cache' => array(
-        'description' => "The time of this user's last post. This is used when the site has specified a minimum_cache_lifetime. See DrupalCacheInterface::get().",
+        'description' => "The time of this user's last post. This is used when the site has specified a minimum_cache_lifetime. See Drupal\Cache\CacheBackendInterface::get().",
         'type' => 'int',
         'not null' => TRUE,
         'default' => 0,