aodh/ceilometer/compute/plugin.py
Akhil Hingane 03c803b5ce VMware vSphere: Improve the accuracy of queried samples
Currently we are querying the latest real time sample from vSphere and
creating a sample out of it, in ceilometer. The sampling interval of
real time samples in vSphere is 20 s. However, the interval at which the
various pollsters are run is by default 600 s (10 mins). This CL
attempts to improve the accuracy of the sample by averaging the samples
over the pollster interval.

Change-Id: Id75fe87840b82d7c7d3e4fae9b2fc982e22ea1d7
Implements: blueprint vmware-vcenter-server
Closes-Bug: 1295500
2014-03-25 19:46:19 +05:30

54 lines
1.8 KiB
Python

# -*- encoding: utf-8 -*-
#
# Copyright © 2012 New Dream Network, LLC (DreamHost)
#
# Author: Doug Hellmann <doug.hellmann@dreamhost.com>
#
# 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.
"""Base class for plugins used by the compute agent.
"""
import abc
import six
from ceilometer.openstack.common import timeutils
from ceilometer import plugin
@six.add_metaclass(abc.ABCMeta)
class ComputePollster(plugin.PollsterBase):
"""Base class for plugins that support the polling API on the compute node.
"""
@abc.abstractmethod
def get_samples(self, manager, cache, resources):
"""Return a sequence of Counter instances from polling the resources.
:param manager: The service manager invoking the plugin
:param cache: A dictionary for passing data between plugins
:param resources: The resources to examine (expected to be instances)
"""
def _record_poll_time(self):
"""Method records current time as the poll time.
:return: time in seconds since the last poll time was recorded
"""
current_time = timeutils.utcnow()
duration = None
if hasattr(self, '_last_poll_time'):
duration = timeutils.delta_seconds(self._last_poll_time,
current_time)
self._last_poll_time = current_time
return duration