Make event-alarm evaluator caching alarms

This patch enables event-alarm evaluator to cache alarms per project
when it get those alarms from the DB. So the evaluator won't access the
DB while the cache exists and does not expired. Cached alarms will be
updated when the alarm fired for consistency.

'event_alarm_cache_ttl' is added to config.

DocImpact

Change-Id: I4e6aa14947cf060c44e82c5f43dc02be586eb855
Implements: blueprint event-alarm-evaluator
This commit is contained in:
Ryota MIBU 2015-08-22 21:51:24 +09:00
parent c9155d4160
commit 217723ce6c
3 changed files with 118 additions and 12 deletions

View File

@ -17,7 +17,9 @@ import copy
import fnmatch
import operator
from oslo_config import cfg
from oslo_log import log
from oslo_utils import timeutils
from aodh import evaluator
from aodh.i18n import _, _LE
@ -33,9 +35,20 @@ COMPARATORS = {
'ne': operator.ne,
}
OPTS = [
cfg.IntOpt('event_alarm_cache_ttl',
default=60,
help='TTL of event alarm caches, in seconds. '
'Set to 0 to disable caching.'),
]
class EventAlarmEvaluator(evaluator.Evaluator):
def __init__(self, conf, notifier):
super(EventAlarmEvaluator, self).__init__(conf, notifier)
self.caches = {}
def evaluate_events(self, events):
"""Evaluate the events by referring related alarms."""
@ -52,10 +65,7 @@ class EventAlarmEvaluator(evaluator.Evaluator):
continue
project = self._get_project(event)
# TODO(r-mibu): cache alarms to reduce DB accesses
alarms = self._storage_conn.get_alarms(enabled=True,
alarm_type='event',
project=project)
alarms = self._get_project_alarms(project)
LOG.debug('Found %(num)d alarms related to the event '
'(message_id=%(id)s)',
{'num': len(alarms), 'id': event['message_id']})
@ -98,6 +108,26 @@ class EventAlarmEvaluator(evaluator.Evaluator):
return trait[2]
return ''
def _get_project_alarms(self, project):
if self.conf.event_alarm_cache_ttl and project in self.caches:
if timeutils.is_older_than(self.caches[project]['updated'],
self.conf.event_alarm_cache_ttl):
del self.caches[project]
else:
return self.caches[project]['alarms']
alarms = self._storage_conn.get_alarms(enabled=True,
alarm_type='event',
project=project)
if self.conf.event_alarm_cache_ttl:
self.caches[project] = {
'alarms': alarms,
'updated': timeutils.utcnow()
}
return alarms
@staticmethod
def _sanitize(event):
"""Change traits format to dict."""
@ -164,6 +194,18 @@ class EventAlarmEvaluator(evaluator.Evaluator):
reason_data = {'type': 'event', 'event': event}
self._refresh(alarm, state, reason, reason_data)
def _refresh(self, alarm, state, reason, reason_data):
super(EventAlarmEvaluator, self)._refresh(alarm, state,
reason, reason_data)
project = alarm.project_id
if self.conf.event_alarm_cache_ttl and project in self.caches:
for index, a in enumerate(self.caches[project]['alarms']):
if a.alarm_id == alarm.alarm_id:
alarm.state = state
self.caches[project]['alarms'][index] = alarm
break
# NOTE(r-mibu): This method won't be used, but we have to define here in
# order to overwrite the abstract method in the super class.
# TODO(r-mibu): Change the base (common) class design for evaluators.

View File

@ -19,6 +19,7 @@ import aodh.api
import aodh.api.controllers.v2.alarms
import aodh.coordination
import aodh.evaluator
import aodh.evaluator.event
import aodh.evaluator.gnocchi
import aodh.event
import aodh.notifier.rest
@ -32,6 +33,7 @@ def list_opts():
('DEFAULT',
itertools.chain(
aodh.evaluator.OPTS,
aodh.evaluator.event.OPTS,
aodh.evaluator.gnocchi.OPTS,
aodh.event.OPTS,
aodh.notifier.rest.OPTS,

View File

@ -12,9 +12,12 @@
# 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 datetime
import uuid
import mock
from oslo_utils import timeutils
from aodh import evaluator
from aodh.evaluator import event as event_evaluator
@ -55,7 +58,7 @@ class TestEventAlarmEvaluate(base.TestEvaluatorBase):
'traits': kwargs.get('traits', [])}
def _do_test_event_alarm(self, alarms, events,
expect_project_in_query=None,
expect_db_queries=None,
expect_alarm_states=None,
expect_alarm_updates=None,
expect_notifications=None):
@ -63,10 +66,11 @@ class TestEventAlarmEvaluate(base.TestEvaluatorBase):
self.evaluator.evaluate_events(events)
if expect_project_in_query is not None:
self.assertEqual([mock.call(enabled=True,
if expect_db_queries is not None:
expected = [mock.call(enabled=True,
alarm_type='event',
project=expect_project_in_query)],
project=p) for p in expect_db_queries]
self.assertEqual(expected,
self.storage_conn.get_alarms.call_args_list)
if expect_alarm_states is not None:
for expected, alarm in zip(expect_alarm_states, alarms):
@ -91,7 +95,7 @@ class TestEventAlarmEvaluate(base.TestEvaluatorBase):
alarm = self._alarm(project='project1')
event = self._event(traits=[['project_id', 1, 'project1']])
self._do_test_event_alarm([alarm], [event],
expect_project_in_query='project1',
expect_db_queries=['project1'],
expect_alarm_states=[evaluator.ALARM],
expect_alarm_updates=[alarm],
expect_notifications=[dict(alarm=alarm,
@ -101,7 +105,7 @@ class TestEventAlarmEvaluate(base.TestEvaluatorBase):
alarm = self._alarm(project='project1')
event = self._event(traits=[['tenant_id', 1, 'project1']])
self._do_test_event_alarm([alarm], [event],
expect_project_in_query='project1',
expect_db_queries=['project1'],
expect_alarm_states=[evaluator.ALARM],
expect_alarm_updates=[alarm],
expect_notifications=[dict(alarm=alarm,
@ -111,7 +115,7 @@ class TestEventAlarmEvaluate(base.TestEvaluatorBase):
alarm = self._alarm(project='')
event = self._event()
self._do_test_event_alarm([alarm], [event],
expect_project_in_query='',
expect_db_queries=[''],
expect_alarm_states=[evaluator.ALARM],
expect_alarm_updates=[alarm],
expect_notifications=[dict(alarm=alarm,
@ -214,3 +218,61 @@ class TestEventAlarmEvaluate(base.TestEvaluatorBase):
expect_alarm_states=[evaluator.UNKNOWN],
expect_alarm_updates=[],
expect_notifications=[])
def test_event_alarm_cache_hit(self):
alarm = self._alarm(project='project2', event_type='none')
events = [
self._event(traits=[['project_id', 1, 'project2']]),
self._event(traits=[['project_id', 1, 'project2']]),
]
self._do_test_event_alarm([alarm], events,
expect_db_queries=['project2'])
def test_event_alarm_cache_updated_after_fired(self):
alarm = self._alarm(project='project2', event_type='type1',
repeat=False)
events = [
self._event(event_type='type1',
traits=[['project_id', 1, 'project2']]),
self._event(event_type='type1',
traits=[['project_id', 1, 'project2']]),
]
self._do_test_event_alarm([alarm], events,
expect_db_queries=['project2'],
expect_alarm_states=[evaluator.ALARM],
expect_alarm_updates=[alarm],
expect_notifications=[dict(alarm=alarm,
event=events[0])])
def test_event_alarm_caching_disabled(self):
alarm = self._alarm(project='project2', event_type='none')
events = [
self._event(traits=[['project_id', 1, 'project2']]),
self._event(traits=[['project_id', 1, 'project2']]),
]
self.evaluator.conf.event_alarm_cache_ttl = 0
self._do_test_event_alarm([alarm], events,
expect_db_queries=['project2', 'project2'])
@mock.patch.object(timeutils, 'utcnow')
def test_event_alarm_cache_expired(self, mock_utcnow):
alarm = self._alarm(project='project2', event_type='none')
events = [
self._event(traits=[['project_id', 1, 'project2']]),
self._event(traits=[['project_id', 1, 'project2']]),
]
mock_utcnow.side_effect = [
datetime.datetime(2015, 1, 1, 0, 0, 0),
datetime.datetime(2015, 1, 1, 1, 0, 0),
datetime.datetime(2015, 1, 1, 1, 1, 0),
]
self._do_test_event_alarm([alarm], events,
expect_db_queries=['project2', 'project2'])
def test_event_alarm_cache_miss(self):
events = [
self._event(traits=[['project_id', 1, 'project2']]),
self._event(traits=[['project_id', 1, 'project3']]),
]
self._do_test_event_alarm([], events,
expect_db_queries=['project2', 'project3'])