diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 55a3875..8f2345c 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -1402,7 +1402,7 @@ function drupal_serve_page_from_cache(stdClass $cache) {
   // response to reply to a subsequent request for a given URL without
   // revalidation. If a Vary header has been set in hook_boot(), it is assumed
   // that the module knows how to cache the page.
-  if (!isset($hook_boot_headers['vary']) && !variable_get('omit_vary_cookie')) {
+  if (!isset($hook_boot_headers['vary']) && !config('system.performance')->get('cache.page.omit_vary_cookie')) {
     header('Vary: Cookie');
   }
 
diff --git a/core/modules/system/config/system.performance.yml b/core/modules/system/config/system.performance.yml
index 7483921..7898f37 100644
--- a/core/modules/system/config/system.performance.yml
+++ b/core/modules/system/config/system.performance.yml
@@ -1,6 +1,7 @@
 cache:
   page:
     enabled: '0'
+    omit_vary_cookie: ''
     max_age: '0'
 preprocess:
   css: '0'
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 5fb624a..109ab67 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -2305,6 +2305,18 @@ function system_update_8039() {
 }
 
 /**
+ * Coverts omit_vary_cookie variable to config.
+ *
+ * @ingroup config_upgrade
+ */
+function system_update_8040() {
+  update_variables_to_config('system.performance', array(
+    'omit_vary_cookie' => 'omit_vary_cookie',
+  ));
+}
+
+
+/**
  * @} End of "defgroup updates-7.x-to-8.x".
  * The next series of updates should start at 9000.
  */
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index 20f4490..6cd1e8f 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -444,7 +444,7 @@
  * HTTP proxy, and bypass the reverse proxy if one is used) in order to avoid
  * getting cached pages from the proxy.
  */
-# $conf['omit_vary_cookie'] = TRUE;
+# $conf['system.performance']['cache.page.omit_vary_cookie'] = TRUE;
 
 /**
  * CSS/JS aggregated file gzip compression: