ZhiQiang Fan 98b43aad17 Return a meaningful value or raise an excpetion for libvirt
Currently, there are some cases libvirt cannot inspect instance's memory
usage, and it is a normal behavior so libvirt just logs messages and
returns None. However, memory pollster doesn't check return value, so
AttributeError will be raised in such case, which leading to unnecessary
exception log messages in every cycle and for each instance, this will
bother cloud operator.

This patch uses virt.inspector exceptions for libvirt, so when there is no
valid value can be returned, we raise an exception, pollsters can catch
those exceptions and log proper messages. Since all of them are non-fatal
exception, log level is set to warn, which is excatly same as previous.

Note, this patch refactors some code of libvirt to suit this change.

Change-Id: I2c94aab90e827c75a602403d3c64fd6f67f73007
Closes-Bug: #1393415
2015-01-08 02:45:53 +08:00

67 lines
2.5 KiB
Python

# Copyright (c) 2014 VMware, Inc.
# 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 mock
from ceilometer.agent import manager
from ceilometer.compute.pollsters import memory
from ceilometer.compute.virt import inspector as virt_inspector
from ceilometer.tests.compute.pollsters import base
class TestMemoryPollster(base.TestPollsterBase):
def setUp(self):
super(TestMemoryPollster, self).setUp()
@mock.patch('ceilometer.pipeline.setup_pipeline', mock.MagicMock())
def test_get_samples(self):
next_value = iter((
virt_inspector.MemoryUsageStats(usage=1.0),
virt_inspector.MemoryUsageStats(usage=2.0),
virt_inspector.NoDataException(),
virt_inspector.InstanceShutOffException(),
))
def inspect_memory_usage(instance, duration):
value = next(next_value)
if isinstance(value, virt_inspector.MemoryUsageStats):
return value
else:
raise value
self.inspector.inspect_memory_usage = mock.Mock(
side_effect=inspect_memory_usage)
mgr = manager.AgentManager()
pollster = memory.MemoryUsagePollster()
@mock.patch('ceilometer.compute.pollsters.memory.LOG')
def _verify_memory_metering(expected_count, expected_memory_mb, mylog):
samples = list(pollster.get_samples(mgr, {}, [self.instance]))
self.assertEqual(expected_count, len(samples))
if expected_count > 0:
self.assertEqual(set(['memory.usage']),
set([s.name for s in samples]))
self.assertEqual(expected_memory_mb, samples[0].volume)
else:
self.assertEqual(1, mylog.warn.call_count)
self.assertEqual(0, mylog.exception.call_count)
_verify_memory_metering(1, 1.0)
_verify_memory_metering(1, 2.0)
_verify_memory_metering(0, 0)
_verify_memory_metering(0, 0)