diff --git a/core/scripts/run-tests.sh b/core/scripts/run-tests.sh
index 5ebf9f0c9f..003f17ca88 100755
--- a/core/scripts/run-tests.sh
+++ b/core/scripts/run-tests.sh
@@ -44,7 +44,7 @@
 
 // Set defaults and get overrides.
 list($args, $count) = simpletest_script_parse_args();
-
+$args['concurrency'] = 48;
 if ($args['help'] || $count == 0) {
   simpletest_script_help();
   exit(($count == 0) ? SIMPLETEST_SCRIPT_EXIT_FAILURE : SIMPLETEST_SCRIPT_EXIT_SUCCESS);
diff --git a/index.php b/index.php
index 750dc282dc..039f8cfb76 100644
--- a/index.php
+++ b/index.php
@@ -20,3 +20,4 @@
 $response->send();
 
 $kernel->terminate($request, $response);
+apcu_clear_cache();