diff --git a/application/common/lib/SystemMonitor.php b/application/common/lib/SystemMonitor.php
index 1a41c8a..dc9caf7 100644
--- a/application/common/lib/SystemMonitor.php
+++ b/application/common/lib/SystemMonitor.php
@@ -47,7 +47,8 @@ static public function getLatest($hash) {
         $hashes = is_array($hash)?$hash:[$hash];
 
         foreach ($hashes as $h){
-            $stat[$h] = array_pop(array_keys(self::getCollection($h)));
+            $info = array_keys(self::getCollection($h));
+            $stat[$h] = array_pop($info);
 
             if(!is_array($hash)) return $stat[$h];
         }