diff --git a/Tests/cachefileTest.php b/Tests/cachefileTest.php
index cc850e5..712f9f5 100644
--- a/Tests/cachefileTest.php
+++ b/Tests/cachefileTest.php
@@ -70,6 +70,7 @@ class test_cachefile extends PHPUnit_Framework_TestCase
   }
 
   // Previous cache in time file but lock : return content after lock timeout
+  // This test takes 10s to wait the lock which will never be released
   public function testRead4 ()
   {
     $c = new cachefile ();