diff --git a/benchmark.py b/benchmark.py
index 4e1a975..fc62527 100644
--- a/benchmark.py
+++ b/benchmark.py
@@ -131,12 +131,17 @@ def get_tree_size(path):
     return size
 
 
+def clear_system_cache():
+    os.system("sudo bash -c 'echo 3 > /proc/sys/vm/drop_caches'")
+
+
 def benchmark(path, get_size=False):
     sizes = {}
 
     if get_size:
         def do_os_walk():
             size = 0
+            clear_system_cache()
             for root, dirs, files in os_walk_func(path):
                 for filename in files:
                     fullname = os.path.join(root, filename)
@@ -144,20 +149,23 @@ def benchmark(path, get_size=False):
             sizes['os_walk'] = size
 
         def do_scandir_walk():
+            clear_system_cache()
             sizes['scandir_walk'] = get_tree_size(path)
 
     else:
         def do_os_walk():
+            clear_system_cache()
             for root, dirs, files in os_walk_func(path):
                 pass
 
         def do_scandir_walk():
+            clear_system_cache()
             for root, dirs, files in scandir.walk(path):
                 pass
 
     # Run this once first to cache things, so we're not benchmarking I/O
-    print("Priming the system's cache...")
-    do_scandir_walk()
+    #print("Priming the system's cache...")
+    #do_scandir_walk()
 
     # Use the best of 3 time for each of them to eliminate high outliers
     os_walk_time = 1000000
diff --git a/scandir.py b/scandir.py
index a3d75be..8453f4d 100644
--- a/scandir.py
+++ b/scandir.py
@@ -466,6 +466,7 @@ elif sys.platform.startswith(('linux', 'darwin')) or 'bsd' in sys.platform:
         def __init__(self, scandir_path, name, d_type):
             self._scandir_path = scandir_path
             self.name = name
+            #assert self._d_type != DT_UNKNOWN
             self._d_type = d_type
             self._stat = None
             self._lstat = None