diff --git a/cassandra/timestamps.py b/cassandra/timestamps.py
index e9602e16..87cf47b4 100644
--- a/cassandra/timestamps.py
+++ b/cassandra/timestamps.py
@@ -53,7 +53,7 @@ class MonotonicTimestampGenerator(object):
     Defaults to 1 second.
     """
 
-    def __init__(self, warn_on_drift=True, warning_threshold=0, warning_interval=0):
+    def __init__(self, warn_on_drift=True, warning_threshold=warning_threshold, warning_interval=warning_interval):
         self.lock = Lock()
         with self.lock:
             self.last = 0
@@ -97,7 +97,7 @@ class MonotonicTimestampGenerator(object):
         since_last_warn = now - self._last_warn
 
         warn = (self.warn_on_drift and
-                (diff > self.warning_threshold * 1e6) and
+                (diff >= self.warning_threshold * 1e6) and
                 (since_last_warn >= self.warning_interval * 1e6))
         if warn:
             log.warn(
diff --git a/tests/unit/test_timestamps.py b/tests/unit/test_timestamps.py
index c2f8b93d..67a82a62 100644
--- a/tests/unit/test_timestamps.py
+++ b/tests/unit/test_timestamps.py
@@ -123,7 +123,10 @@ class TestTimestampGeneratorLogging(unittest.TestCase):
 
         @test_category timing
         """
-        tsg = timestamps.MonotonicTimestampGenerator()
+        tsg = timestamps.MonotonicTimestampGenerator(
+            warning_threshold=1e-6,
+            warning_interval=1e-6
+        )
         #The units of _last_warn is seconds
         tsg._last_warn = 12
 
@@ -181,7 +184,8 @@ class TestTimestampGeneratorLogging(unittest.TestCase):
         @test_category timing
         """
         tsg = timestamps.MonotonicTimestampGenerator(
-            warning_threshold=1e-6
+            warning_threshold=1e-6,
+            warning_interval=1e-6
         )
         tsg.last, tsg._last_warn = 100, 97
         tsg._next_timestamp(98, tsg.last)
@@ -198,6 +202,7 @@ class TestTimestampGeneratorLogging(unittest.TestCase):
         @test_category timing
         """
         tsg = timestamps.MonotonicTimestampGenerator(
+            warning_threshold=1e-6,
             warning_interval=2e-6
         )
         tsg.last = 100
@@ -219,7 +224,8 @@ class TestTimestampGeneratorLogging(unittest.TestCase):
         @test_category timing
         """
         tsg = timestamps.MonotonicTimestampGenerator(
-            warning_interval=1e-6
+            warning_interval=1e-6,
+            warning_threshold=1e-6,
         )
         tsg.last = 100
         tsg._next_timestamp(70, tsg.last)
@@ -249,7 +255,7 @@ class TestTimestampGeneratorMultipleThreads(unittest.TestCase):
                 with lock:
                     generated_timestamps.append(timestamp)
 
-        tsg = timestamps.MonotonicTimestampGenerator(warning_threshold=1)
+        tsg = timestamps.MonotonicTimestampGenerator()
         fixed_time = 1
         num_threads = 5