diff --git a/Tools/pybench/pybench.py b/Tools/pybench/pybench.py
index e1bc95d05d8..83a62173c64 100755
--- a/Tools/pybench/pybench.py
+++ b/Tools/pybench/pybench.py
@@ -501,6 +501,7 @@ def load_tests(self, setupmod, limitnames=None):
     def calibrate(self):
 
         print 'Calibrating tests. Please wait...',
+        sys.stdout.flush()
         if self.verbose:
             print
             print