compute CDM include all instances¶
https://blueprints.launchpad.net/watcher/+spec/compute-cdm-include-all-instances
Problem description¶
When building compute CDM, we will exclude the instances excluded by the scope. It has terrible impact to Watcher.
To workload balance and server consolidation, the excluded instances in the scope are not added into the workload. So it would get incorrectly workload of the compute nodes, and execute unreasonbale migrations.
To server consolidation, it would disable the nodes which still have excluded instances running.
Use Cases¶
As an end user, I want Watcher to take excluded instances into account during workload calculations but not migrate excluded instances.
Proposed change¶
Watcher should have a whole scope of the cluster, include all instances. So it would get the correct workload of the nodes, and make the correct optimization.
Compute CDM in Watcher should has a whole scope, include all instances. It needs to be clear which instances are exclude and which are not.
We can add “watcher_exclude” field to “Instance” resource to distinguish them, as following.
- class Instance(compute_resource.ComputeResource):
- fields = {
“watcher_exclude”: wfields.BooleanField(default=False), “state”: wfields.StringField(default=InstanceState.ACTIVE.value), …
}
When building compute CDM, set the ‘watcher_exclude’ flag ‘True’ if the instance is excluded by the scope.
Alternatives¶
None
Data model impact¶
None
REST API impact¶
None
Security impact¶
None
Notifications impact¶
None
Other end user impact¶
None
Performance Impact¶
None
Other deployer impact¶
None
Developer impact¶
None
Implementation¶
Assignee(s)¶
Primary assignee: sue
Work Items¶
Add and identify excluded instances in compute CDM
Adjust workload balance and server consolidation, when calculating workload of the compute nodes and generating solutions
Dependencies¶
Testing¶
Unit test
Documentation Impact¶
None
References¶
https://docs.openstack.org/watcher/latest/glossary.html#cluster-data-model-definition
History¶
None
