diff --git a/python/ray/monitor.py b/python/ray/monitor.py
index eb86443c9..ae7903261 100644
--- a/python/ray/monitor.py
+++ b/python/ray/monitor.py
@@ -283,7 +283,8 @@ class Monitor(object):
                             continue
 
                 log.info("Driver {} is returning GPU IDs {} to local "
-                         "scheduler {}.".format(driver_id, num_gpus_returned,
+                         "scheduler {}.".format(binary_to_hex(driver_id),
+                                                num_gpus_returned,
                                                 local_scheduler_id))
 
     def process_messages(self):
diff --git a/test/actor_test.py b/test/actor_test.py
index 8032b0774..b9b0f65a4 100644
--- a/test/actor_test.py
+++ b/test/actor_test.py
@@ -858,10 +858,14 @@ class ActorsWithGPUs(unittest.TestCase):
                     second_interval = list_of_intervals[j]
                     # Check that list_of_intervals[i] and list_of_intervals[j]
                     # don't overlap.
-                    assert first_interval[0] < first_interval[1]
-                    assert second_interval[0] < second_interval[1]
-                    assert (first_interval[1] < second_interval[0] or
-                            second_interval[1] < first_interval[0])
+                    self.assertLess(first_interval[0], first_interval[1])
+                    self.assertLess(second_interval[0], second_interval[1])
+                    intervals_nonoverlapping = (
+                        first_interval[1] <= second_interval[0] or
+                        second_interval[1] <= first_interval[0])
+                    assert intervals_nonoverlapping, (
+                        "Intervals {} and {} are overlapping."
+                        .format(first_interval, second_interval))
 
         @ray.remote(num_gpus=1)
         def f1():