Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

Bug 2120756

Summary:	[17.0 ga tech preview] Count quota usage from placement
Product:	Red Hat OpenStack	Reporter:	Artom Lifshitz <alifshit>
Component:	openstack-nova	Assignee:	OSP DFG:Compute <osp-dfg-compute>
Status:	CLOSED CURRENTRELEASE	QA Contact:	OSP DFG:Compute <osp-dfg-compute>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	16.0 (Train)	CC:	dasmith, eglynn, igallagh, jamsmith, jhakimra, kchamart, mgeary, sbauza, sgordon, vromanso
Target Milestone:	ga	Keywords:	Triaged
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Technology Preview
Doc Text:	In Red Hat OpenStack Platform 17.0, a technology preview is available to configure counting of quota usage of cores and ram by querying placement for resource usage and instances from instance mappings in the API database, instead of counting resources from separate cell databases. This makes quota usage counting resilient to temporary cell outages or poor cell performance in a multi-cell environment. + Set the following configuration option to count quota usage from placement: + ``` parameter_defaults: ControllerExtraConfig: nova::config::nova_config: quota/count_usage_from_placement: value: 'True' ```	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-09-12 15:22:58 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Artom Lifshitz 2022-08-23 16:46:43 UTC

This bug was initially created as a copy of Bug #1720404

I am copying this bug because: 

Tech preview release note because lack of QE capacity.

In Pike, we re-architected the quota system to count actual resource usage instead of using reservations and tracking quota usages in a separate database table. We're counting resources like instances, CPU, and RAM by querying each cell database and aggregating the results per project and per user. This approach has a downside: it is susceptible to undesirable behavior if a cell becomes unavailable. If a cell becomes unavailable, resources in its database cannot be counted and will not be included in resource usage until the cell returns. Cells could become unavailable if an operator is performing maintenance on a cell or if a cell database is experiencing problems and we cannot connect to it.

We can make resource usage counting for quotas resilient to temporary cell outages by querying placement for resource usage instead of reading separate cell databases.

This adds the ability to count quota usage from placement on an opt-in basis via configuration option.

Comment 2 Artom Lifshitz 2022-09-12 15:22:58 UTC

The release notes automation will pick up BZs with the right flags even if they're closed. With the doc text done and requires_doc_text set to +, we can close this.

Comment 5 Red Hat Bugzilla 2023-09-18 04:45:19 UTC

The needinfo request[s] on this closed bug have been removed as they have been unresolved for 120 days