diff --git a/taskflow/tests/unit/test_utils_lock_utils.py b/taskflow/tests/unit/test_utils_lock_utils.py
index 475ee059b..30a120a37 100644
--- a/taskflow/tests/unit/test_utils_lock_utils.py
+++ b/taskflow/tests/unit/test_utils_lock_utils.py
@@ -28,6 +28,9 @@ from taskflow.utils import lock_utils
 # real overlaps then they will still exist.
 NAPPY_TIME = 0.05
 
+# We will spend this amount of time doing some "fake" work.
+WORK_TIMES = [(0.01 + x/100.0) for x in range(0, 5)]
+
 
 def _find_overlaps(times, start, end):
     overlaps = 0
@@ -41,29 +44,41 @@ def _spawn_variation(readers, writers, max_workers=None):
     start_stops = collections.deque()
     lock = lock_utils.ReaderWriterLock()
 
-    def read_func():
+    def read_func(ident):
         with lock.read_lock():
-            start_stops.append(('r', time.time(), time.time()))
+            # TODO(harlowja): sometime in the future use a monotonic clock here
+            # to avoid problems that can be caused by ntpd resyncing the clock
+            # while we are actively running.
+            enter_time = time.time()
+            time.sleep(WORK_TIMES[ident % len(WORK_TIMES)])
+            exit_time = time.time()
+            start_stops.append((lock.READER, enter_time, exit_time))
             time.sleep(NAPPY_TIME)
 
-    def write_func():
+    def write_func(ident):
         with lock.write_lock():
-            start_stops.append(('w', time.time(), time.time()))
+            enter_time = time.time()
+            time.sleep(WORK_TIMES[ident % len(WORK_TIMES)])
+            exit_time = time.time()
+            start_stops.append((lock.WRITER, enter_time, exit_time))
             time.sleep(NAPPY_TIME)
 
     if max_workers is None:
         max_workers = max(0, readers) + max(0, writers)
     if max_workers > 0:
         with futures.ThreadPoolExecutor(max_workers=max_workers) as e:
-            for i in range(0, readers):
-                e.submit(read_func)
-            for i in range(0, writers):
-                e.submit(write_func)
+            count = 0
+            for _i in range(0, readers):
+                e.submit(read_func, count)
+                count += 1
+            for _i in range(0, writers):
+                e.submit(write_func, count)
+                count += 1
 
     writer_times = []
     reader_times = []
-    for (t, start, stop) in list(start_stops):
-        if t == 'w':
+    for (lock_type, start, stop) in list(start_stops):
+        if lock_type == lock.WRITER:
             writer_times.append((start, stop))
         else:
             reader_times.append((start, stop))