diff --git a/core/lib/Drupal/Core/Cache/ApcuBackend.php b/core/lib/Drupal/Core/Cache/ApcuBackend.php
index 9670e01..f6de468 100644
--- a/core/lib/Drupal/Core/Cache/ApcuBackend.php
+++ b/core/lib/Drupal/Core/Cache/ApcuBackend.php
@@ -62,8 +62,8 @@ class ApcuBackend implements CacheBackendInterface {
   public function __construct($bin, $site_prefix) {
     $this->bin = $bin;
     $this->sitePrefix = $site_prefix;
-    $this->binPrefix = $this->sitePrefix . $this->bin . '::';
-    $this->tagsPrefix = $this->sitePrefix . 'tags::';
+    $this->binPrefix = $this->sitePrefix . '::' . $this->bin . '::';
+    $this->tagsPrefix = $this->sitePrefix . '::tags::';
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Cache/ApcuBackendFactory.php b/core/lib/Drupal/Core/Cache/ApcuBackendFactory.php
index a18fc6f..6c6d4ba 100644
--- a/core/lib/Drupal/Core/Cache/ApcuBackendFactory.php
+++ b/core/lib/Drupal/Core/Cache/ApcuBackendFactory.php
@@ -10,6 +10,20 @@
 class ApcuBackendFactory implements CacheFactoryInterface {
 
   /**
+   * The site prefix string.
+   *
+   * @var string
+   */
+  protected $sitePrefix;
+
+  /**
+   * Constructs an ApcuBackendFactory object.
+   */
+  public function __construct() {
+    $this->sitePrefix = md5(DRUPAL_ROOT . '/' . conf_path());
+  }
+
+  /**
    * Gets ApcuBackend for the specified cache bin.
    *
    * @param $bin
@@ -18,8 +32,8 @@ class ApcuBackendFactory implements CacheFactoryInterface {
    * @return \Drupal\Core\Cache\ApcuBackend
    *   The cache backend object for the specified cache bin.
    */
-  function get($bin) {
-    return new ApcuBackend($bin, conf_path());
+  public function get($bin) {
+    return new ApcuBackend($bin, $this->sitePrefix);
   }
 
 }