deb-ceilometer/ceilometer/compute/discovery.py
Ilya Tyaptin 45ef4699c7 Add an update interval to compute discovery
This option allows to collect nova-api resource not on every polling.
It's useful for the fast polling of the created instances and allow
to reduce nova-api requests count.

Change-Id: I0d163f83287a4f2ce065d3e1d930c92b1addef35
Partially-implements: improve-nova-instance-metering
2016-02-26 14:44:25 +03:00

88 lines
3.4 KiB
Python

#
# Copyright 2014 Red Hat, Inc
#
# 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.
from oslo_config import cfg
from oslo_utils import timeutils
from ceilometer.agent import plugin_base
from ceilometer import nova_client
OPTS = [
cfg.BoolOpt('workload_partitioning',
default=False,
help='Enable work-load partitioning, allowing multiple '
'compute agents to be run simultaneously.'),
cfg.IntOpt('resource_update_interval',
default=0,
min=0,
help="New instances will be discovered periodically based"
" on this option (in seconds). By default, "
"the agent discovers instances according to pipeline "
"polling interval. If option is greater than 0, "
"the instance list to poll will be updated based "
"on this option's interval. Measurements relating "
"to the instances will match intervals "
"defined in pipeline.")
]
cfg.CONF.register_opts(OPTS, group='compute')
class InstanceDiscovery(plugin_base.DiscoveryBase):
def __init__(self):
super(InstanceDiscovery, self).__init__()
self.nova_cli = nova_client.Client()
self.last_run = None
self.instances = {}
self.expiration_time = cfg.CONF.compute.resource_update_interval
def discover(self, manager, param=None):
"""Discover resources to monitor."""
secs_from_last_update = 0
if self.last_run:
secs_from_last_update = timeutils.delta_seconds(
self.last_run, timeutils.utcnow(True))
instances = []
# NOTE(ityaptin) we update make a nova request only if
# it's a first discovery or resources expired
if not self.last_run or secs_from_last_update >= self.expiration_time:
try:
utc_now = timeutils.utcnow(True)
since = self.last_run.isoformat() if self.last_run else None
instances = self.nova_cli.instance_get_all_by_host(
cfg.CONF.host, since)
self.last_run = utc_now
except Exception:
# NOTE(zqfan): instance_get_all_by_host is wrapped and will log
# exception when there is any error. It is no need to raise it
# again and print one more time.
return []
for instance in instances:
if getattr(instance, 'OS-EXT-STS:vm_state', None) in ['deleted',
'error']:
self.instances.pop(instance.id, None)
else:
self.instances[instance.id] = instance
return self.instances.values()
@property
def group_id(self):
if cfg.CONF.compute.workload_partitioning:
return cfg.CONF.host
else:
return None