Merge "Make eventlet hub use a monotonic clock"

masakari/__init__.py

@@ -26,4 +26,9 @@ import os
 
 os.environ['EVENTLET_NO_GREENDNS'] = 'yes'
 
+# NOTE(rpodolyaka): import oslo_service first, so that it makes eventlet hub
+# use a monotonic clock to avoid issues with drifts of system time (see
+# LP 1510234 for details)
+import oslo_service  # noqa
+
 import eventlet  # noqa

masakari/service.py

@@ -41,6 +41,17 @@ LOG = logging.getLogger(__name__)
 CONF = masakari.conf.CONF
 
 
+def assert_eventlet_uses_monotonic_clock():
+    import eventlet.hubs as 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.
 
@@ -78,6 +89,7 @@ class Service(service.Service):
                }
 
     def start(self):
+        assert_eventlet_uses_monotonic_clock()
         verstr = version.version_string_with_package()
         LOG.info('Starting %(topic)s (version %(version)s)', {
             'topic': self.topic,