Bug 1547255

Summary: [RFE] Utilize placement to increase scheduler performance
Product: Red Hat OpenStack Reporter: Dan Smith <dasmith>
Component: openstack-novaAssignee: Dan Smith <dasmith>
Status: CLOSED ERRATA QA Contact: Joe H. Rahme <jhakimra>
Severity: high Docs Contact:
Priority: high    
Version: 14.0 (Rocky)CC: berrange, dasmith, eglynn, igallagh, kchamart, lyarwood, sbauza, sgordon, srevivo, vromanso
Target Milestone: Upstream M2Keywords: FutureFeature, Triaged
Target Release: 14.0 (Rocky)   
Hardware: Unspecified   
OS: Unspecified   
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Fixed In Version: openstack-nova-18.0.0-0.20180710150340.8469fa7 Doc Type: If docs needed, set a value
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Clone Of: Environment:
Last Closed: 2019-01-11 11:48:58 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Dan Smith 2018-02-20 21:10:17 UTC
Description of problem:

Now that placement is deployed, populated, and capable of answering more complex queries, we should utilize it to reduce the workload on the nova scheduler. The scheduler must filter large numbers of hosts down to very few during boot or migration actions, and is often the choke point for these operations.

Specifically, the introduction of CellsV2 allows/requires deployments to have a single scheduler (or set of schedulers) for all of their compute hosts. Especially given the default limit of 1000 results from placement, the scheduler may not even be able to provide good answers to scheduling queries due to it asking overly vague questions of placement.

We need a way to augment our queries to placement in order to receive smaller and more relevant sets of hosts from it, against which we apply our filters.

Comment 11 errata-xmlrpc 2019-01-11 11:48:58 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2019:0045

Comment 12 Red Hat Bugzilla 2023-09-14 04:16:52 UTC
The needinfo request[s] on this closed bug have been removed as they have been unresolved for 1000 days