f606dce80c
This commit includes small changes to fix Sphinx warnings and a specs template file for the Train release. Change-Id: Ifb44a1d948f8fcd6db95b154a84ed18e3ee4b042
3.3 KiB
Update a capacity of reserved resource
https://blueprints.launchpad.net/blazar/+spec/update-reserved-capacity
Support updating the capacity of an existing reservation.
Problem description
The start date and the end date of a lease can be updated through the update lease request. However, the capacity of reserved resource cannot be changed once the reservation is created for now. The capacity should be able to be changed for improving the flexibility of resource usage requests.
Use Cases
- As Wei, I want to be able to query/update/terminate a resource usage request at any point in time. (Required in the capacity management development proposal[1])
Proposed change
The update_reservation() method of a resource plugin currently checks only the start_date and end_date of the request body. Change it to check other parameters, e.g., min, max, hypervisor_properties and resource_properties for the host plugin. And enable the update_reservation() method to update allocations.
The update_reservation() succeeds if all of the request parameters can be satisfied. Otherwise, it raises exceptions.
First target is the host plugin. For the host plugin, min, max, hypervisor_properties and resource_properties can be updated if an update request satisfies all of following conditions:
- Enough resources are available for the new request.
- Any host does not removed from the aggregate associated with the lease if the lease has already started. This condition is needed for preventing unexpected deletion and error of instances on the reserved host.
Otherwise, Blazar returns an error and nothing is updated.
Alternatives
None.
Data model impact
None.
REST API impact
- Users send a update-lease request with some parameters that they want to update.
Security impact
None.
Notifications impact
None.
Other end user impact
None.
Performance Impact
The resource allocation algorithm of resource plugins can be more complex. So the performance impact should be carefully tested.
Other deployer impact
None.
Developer impact
Developers of new resource plugins should consider this capability for the update_reservation() method.
Implementation
Assignee(s)
- Primary assignee:
-
hiro-kobayashi
Work Items
- Change the update_reservation() method of the host plugin.
Dependencies
None
Testing
- Adds unit tests of update capacity request for the update_reservation() method
- Adds scenario test of update capacity request
Documentation Impact
Write a release note.
References
- Capacity management development proposal: http://git.openstack.org/cgit/openstack/development-proposals/tree/development-proposals/proposed/capacity-management.rst
History
| Release Name | Description |
|---|---|
| Pike | Introduced |