neutron/neutron/agent/common/polling.py
Lucian Petrut 585b6f0af7 Windows OVS: minimize polling
Now, that the ovsdb monitor is also available on Windows, we can
use it on Windows as well, minimizing polling.

We're simply moving the bits to the common polling module.

Change-Id: Ia12ad970085f2cff8c8ac5b7d3d69e7dc9214c40
2018-08-14 09:54:07 +03:00

76 lines
2.4 KiB
Python

# Copyright 2015 Cloudbase Solutions.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import contextlib
import eventlet
from oslo_config import cfg
from oslo_log import log as logging
from neutron.agent.common import async_process
from neutron.agent.common import base_polling
from neutron.agent.common import ovsdb_monitor
from neutron.plugins.ml2.drivers.openvswitch.agent.common import constants
LOG = logging.getLogger(__name__)
@contextlib.contextmanager
def get_polling_manager(minimize_polling=False,
ovsdb_monitor_respawn_interval=(
constants.DEFAULT_OVSDBMON_RESPAWN)):
if minimize_polling:
pm = InterfacePollingMinimizer(
ovsdb_monitor_respawn_interval=ovsdb_monitor_respawn_interval)
pm.start()
else:
pm = base_polling.AlwaysPoll()
try:
yield pm
finally:
if minimize_polling:
pm.stop()
class InterfacePollingMinimizer(base_polling.BasePollingManager):
"""Monitors ovsdb to determine when polling is required."""
def __init__(
self,
ovsdb_monitor_respawn_interval=constants.DEFAULT_OVSDBMON_RESPAWN):
super(InterfacePollingMinimizer, self).__init__()
self._monitor = ovsdb_monitor.SimpleInterfaceMonitor(
respawn_interval=ovsdb_monitor_respawn_interval,
ovsdb_connection=cfg.CONF.OVS.ovsdb_connection)
def start(self):
self._monitor.start(block=True)
def stop(self):
try:
self._monitor.stop()
except async_process.AsyncProcessException:
LOG.debug("InterfacePollingMinimizer was not running when stopped")
def _is_polling_required(self):
# Maximize the chances of update detection having a chance to
# collect output.
eventlet.sleep()
return self._monitor.has_updates
def get_events(self):
return self._monitor.get_events()