Bug 1921160

Summary:	[Docs] Topology Manager does not require enabling LatencySensitive Feature Gate
Product:	OpenShift Container Platform	Reporter:	Alberto Losada <alosadag>
Component:	Documentation	Assignee:	Michael Burke <mburke>
Status:	CLOSED CURRENTRELEASE	QA Contact:	MinLi <minmli>
Severity:	medium	Docs Contact:	Vikram Goyal <vigoyal>
Priority:	medium
Version:	4.6.z	CC:	aos-bugs, jokerman, mburke, minmli, oarribas
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Last Closed:	2021-05-25 15:30:54 UTC	Type:	Bug
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Description Alberto Losada 2021-01-27 15:56:44 UTC

Document URL: 

https://docs.openshift.com/container-platform/4.6/scalability_and_performance/using-topology-manager.html#seting_up_topology_manager_using-topology-manager

Section Number and Name: 

Setting up Topology Manager

Describe the issue: 

The Feature Gate called LatencySensitive no longer needs to be enabled to configure Topology Manager. Topology Manager feature is already enabled by default since k8s 1.18 (https://kubernetes.io/docs/reference/command-line-tools-reference/feature-gates/#feature-gates-for-alpha-or-beta-features)

So basically, you just need to set the desired topologyManagerPolicy value in kubelet as a KubeletConfig CR.

Suggestions for improvement: 

Remove this part of the documentation, just explain that it is enabled by default since OCP 4.5 (I believe) and I'll also link in some way that the performance addon operator (GA in 4.6 - https://docs.openshift.com/container-platform/4.6/scalability_and_performance/cnf-performance-addon-operator-for-low-latency-nodes.html#cnf-tuning-nodes-for-low-latency-via-performanceprofile_cnf-master) is able to help you configuring topology manager policies and more features related to low latency/real-time. 

Additional information:

Comment 1 Michael Burke 2021-04-09 19:05:50 UTC

Min -- I found this BZ about the `Latencysensitive` feature set not being required to enable Topology Manager. Because `LatencySensitive` seems to affect only that feature, I removed references to the feature set from the Feature Gates docs. Please let me know if this is correct.

Thank you,
Michael

https://github.com/openshift/openshift-docs/pull/24132

Comment 2 MinLi 2021-04-13 08:00:38 UTC

 Michael Burke, the pr LGTM. When it merge, I will move this bz to verified.

Comment 3 Michael Burke 2021-05-25 15:30:54 UTC

Changes are live: https://docs.openshift.com/container-platform/4.7/nodes/clusters/nodes-cluster-enabling-features.html