diff --git a/core/modules/system/lib/Drupal/system/Tests/Upgrade/SystemUpgradePathTest.php b/core/modules/system/lib/Drupal/system/Tests/Upgrade/SystemUpgradePathTest.php
new file mode 100644
index 00000000000..db95f06f1b8
--- /dev/null
+++ b/core/modules/system/lib/Drupal/system/Tests/Upgrade/SystemUpgradePathTest.php
@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\system\Tests\Upgrade\SystemUpgradePathTest.
+ */
+
+namespace Drupal\system\Tests\Upgrade;
+
+/**
+ * Tests upgrade of system variables.
+ */
+class SystemUpgradePathTest extends UpgradePathTestBase {
+  public static function getInfo() {
+    return array(
+      'name' => 'System config upgrade test',
+      'description' => 'Tests upgrade of system variables to the configuration system.',
+      'group' => 'Upgrade path',
+    );
+  }
+
+  public function setUp() {
+    $this->databaseDumpFiles = array(
+      drupal_get_path('module', 'system') . '/tests/upgrade/drupal-7.bare.standard_all.database.php.gz',
+      drupal_get_path('module', 'system') . '/tests/upgrade/drupal-7.system.database.php',
+    );
+    parent::setUp();
+  }
+
+  /**
+   * Tests upgrade of system variables.
+   */
+  public function testSystemVariableUpgrade() {
+    $this->assertTrue($this->performUpgrade(), 'The upgrade was completed successfully.');
+
+    // Verify that variables were properly upgraded.
+    $expected_config['system.cron'] = array(
+      'key' => 'kdm95qppDDlyZrcUOx453YwQqDA4DNmxi4VQcxzFU9M',
+      'threshold.autorun' => '86400',
+      'threshold.requirements_warning' => '86400',
+      'threshold.requirements_error' => '172800',
+    );
+
+    $expected_config['system.logging'] = array(
+      'error_level' => 'some',
+    );
+
+    $expected_config['system.maintenance'] = array(
+      'enabled' => '1',
+      'message' => 'Testing config upgrade',
+    );
+
+    $expected_config['system.performance'] = array(
+      'cache.page.enabled' => '1',
+      'cache.page.max_age' => '1800',
+      'response.gzip' => '1',
+      'preprocess.js' => '1',
+      'preprocess.css' => '1',
+    );
+
+    $expected_config['system.rss'] = array(
+      'channel.description' => 'Testing config upgrade',
+      'items.limit' => '20',
+      'items.view_mode' => 'teaser',
+    );
+
+    $expected_config['system.site'] = array(
+      'name' => 'Testing config upgrade',
+      // The upgrade from site_mail to system.site:mail is not testable as
+      // simpletest overrides this configuration with simpletest@example.com.
+      // 'mail' => 'config@example.com',
+      'slogan' => 'CMI makes Drupal 8 drush cex -y',
+      'page.403' => '403',
+      'page.404' => '404',
+      'page.front' => 'node',
+    );
+
+    foreach ($expected_config as $file => $values) {
+      $config = config($file);
+      $this->verbose(print_r($config->get(), TRUE));
+      foreach ($values as $name => $value) {
+        $stored = $config->get($name);
+        $this->assertEqual($value, $stored, format_string('Expected value for %name found: %stored (previously: %value).', array('%stored' => $stored, '%name' => $name, '%value' => $value)));
+      }
+    }
+  }
+}
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 9f101196df4..4fe99f90182 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -1948,7 +1948,7 @@ function system_update_8016() {
  * @ingroup config_upgrade
  */
 function system_update_8017() {
-  update_variables_to_config('system.site', array(
+  update_variables_to_config('system.performance', array(
     'cache' => 'cache.page.enabled',
     'page_cache_maximum_age' => 'cache.page.max_age',
     'page_compression' => 'response.gzip',
diff --git a/core/modules/system/tests/upgrade/drupal-7.system.database.php b/core/modules/system/tests/upgrade/drupal-7.system.database.php
new file mode 100644
index 00000000000..8afbc12ae84
--- /dev/null
+++ b/core/modules/system/tests/upgrade/drupal-7.system.database.php
@@ -0,0 +1,104 @@
+<?php
+
+/**
+ * @file
+ * Database additions for system tests. Used in upgrade.system.test.
+ *
+ * This dump only contains data and schema components relevant for system
+ * functionality. The drupal-7.filled.bare.php file is imported before
+ * this dump, so the two form the database structure expected in tests
+ * altogether.
+ */
+
+// Add non-default system settings.
+db_insert('variable')->fields(array(
+  'name',
+  'value',
+))
+->values(array(
+  'name' => 'cache',
+  'value'=> 'i:1;',
+))
+->values(array(
+    'name' => 'cache_lifetime',
+    'value' => 's:5:"10800";',
+  ))
+->values(array(
+    'name' => 'page_cache_maximum_age',
+    'value' => 's:4:"1800";',
+  ))
+->values(array(
+    'name' => 'page_compression',
+    'value' => 'i:1;',
+  ))
+->values(array(
+    'name' => 'preprocess_css',
+    'value' => 'i:1;',
+  ))
+->values(array(
+    'name' => 'preprocess_js',
+    'value' => 'i:1;',
+  ))
+->values(array(
+    'name' => 'cron_safe_threshold',
+    'value' => 's:5:"86400";',
+  ))
+->values(array(
+    'name' => 'cron_threshold_warning',
+    'value' => 's:5:"86400";',
+  ))
+->values(array(
+    'name' => 'cron_threshold_error',
+    'value' => 's:6:"172800";',
+  ))
+->values(array(
+    'name' => 'error_level',
+    'value' => 's:1:"1";',
+  ))
+->values(array(
+    'name' => 'maintenance_mode',
+    'value' => 'i:1;',
+  ))
+->values(array(
+    'name' => 'maintenance_mode_message',
+    'value' => 's:22:"Testing config upgrade"',
+  ))
+->values(array(
+    'name' => 'feed_default_items',
+    'value' => 's:2:"20";',
+  ))
+->values(array(
+    'name' => 'feed_description',
+    'value' => 's:22:"Testing config upgrade";',
+  ))
+->values(array(
+    'name' => 'feed_item_length',
+    'value' => 's:6:"teaser";',
+  ))
+->values(array(
+    'name' => 'site_403',
+    'value' => 's:3:"403";',
+  ))
+->values(array(
+    'name' => 'site_404',
+    'value' => 's:3:"404";',
+  ))
+->values(array(
+    'name' => 'site_frontpage',
+    'value' => 's:4:"node";',
+  ))
+->values(array(
+    'name' => 'site_slogan',
+    'value' => 's:31:"CMI makes Drupal 8 drush cex -y";',
+  ))
+->execute();
+
+db_update('variable')
+  ->fields(array('value' => 's:18:"config@example.com";'))
+  ->condition('name', 'site_mail')
+  ->execute();
+db_update('variable')
+    ->fields(array('value' => 's:22:"Testing config upgrade";'))
+    ->condition('name', 'site_name')
+    ->execute();
+