diff --git a/lower-constraints.txt b/lower-constraints.txt
index 10825b9d12..3fb0252734 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -49,7 +49,6 @@ Mako==1.0.7
 MarkupSafe==1.0
 microversion-parse==0.2.1
 mock==3.0.0
-monotonic==1.4
 msgpack==0.5.6
 msgpack-python==0.5.6
 munch==2.2.0
diff --git a/nova/service.py b/nova/service.py
index fd28a71740..5af20ed0b9 100644
--- a/nova/service.py
+++ b/nova/service.py
@@ -92,17 +92,6 @@ def setup_profiler(binary, host):
         LOG.info("OSProfiler is enabled.")
 
 
-def assert_eventlet_uses_monotonic_clock():
-    from eventlet import hubs
-    import monotonic
-
-    hub = hubs.get_hub()
-    if hub.clock is not monotonic.monotonic:
-        raise RuntimeError(
-            'eventlet hub is not using a monotonic clock - '
-            'periodic tasks will be affected by drifts of system time.')
-
-
 class Service(service.Service):
     """Service object for binaries running on hosts.
 
@@ -163,8 +152,6 @@ class Service(service.Service):
         # outside of oslo.db.
         context.CELL_CACHE = {}
 
-        assert_eventlet_uses_monotonic_clock()
-
         verstr = version.version_string_with_package()
         LOG.info('Starting %(topic)s node (version %(version)s)',
                   {'topic': self.topic, 'version': verstr})