Unify the timestamp of samples generated by polling agents¶
https://blueprints.launchpad.net/ceilometer/+spec/unify-timestamp-of-polled-data
Problem description¶
Many of the pollsters define the timestamp individually for each generated sample, which should really be timestamping based on when the data was polled and not when each sample is generated. We need to set the timestamp of the polled data to the timestamp when the polling starts for unity.
This should save overhead of calculating timestamp each sample and also allow for easier grouping of polled data.
Proposed change¶
Modify ceilometer.agent.manager.PollingTask.poll_and_notify method to set the timestamp of samples to the time when the data was polled:
# Get the timestamp when pollster starts to work
polling_timestamp = self._get_current_timestamp()
samples = pollster.obj.get_samples(
manager=self.manager,
cache=cache,
resources=polling_resources
)
for sample in samples:
# Unify the timestamp of polled samples
sample.set_timestamp(polling_timestamp)
Drop all the timestamp generations when we build samples via pollsters, like: https://github.com/openstack/ceilometer/blob/6.0.0.0b2/ceilometer/image/glance.py#L113
Alternatives¶
None
Data model impact¶
None
REST API impact¶
None
Security impact¶
None
Pipeline impact¶
None
Other end user impact¶
None
Performance/Scalability Impacts¶
Save overhead of calculating timestamp each sample.
Other deployer impact¶
None
Developer impact¶
None
Implementation¶
Assignee(s)¶
- Primary assignee:
<yuywz>
Work Items¶
Update ceilometer.agent.manager.PollingTask.poll_and_notify method.
Drop all the timestamp generations when we build samples via pollsters.
Future lifecycle¶
None
Dependencies¶
None
Testing¶
Add unit test to test: The timestamp of samples generated during a polling cycle is unified.
Documentation Impact¶
None
References¶
Originally reported as a bug: https://bugs.launchpad.net/ceilometer/+bug/1491509 Blueprint: https://blueprints.launchpad.net/ceilometer/+spec/unify-timestamp-of-polled-data
