Add last-level cache locality docs for MicroShift (OSDOCS-15553)

microshift_configuring/microshift_low_latency/microshift-low-latency.adoc

@@ -25,6 +25,15 @@ include::modules/microshift-low-latency-config-yaml.adoc[leveloffset=+1]
 * xref:../../microshift_configuring/microshift-using-config-yaml.adoc#microshift-using-config-yaml[Customizing {microshift-short} by using the configuration file]
 * link:https://kubernetes.io/docs/reference/config-api/kubelet-config.v1beta1/#kubelet-config-k8s-io-v1beta1-KubeletConfiguration[KubeletConfiguration reference] (Kubernetes upstream documentation)
 
+include::modules/microshift-low-latency-llc.adoc[leveloffset=+1]
+
+//additional resources for LLC locality
+[role="_additional-resources"]
+.Additional resources
+* link:https://kubernetes.io/docs/tasks/administer-cluster/cpu-management-policies/#static-policy-options[Control CPU Management Policies on the Node - Static policy options (Kubernetes documentation)]
+* xref:../../microshift_configuring/microshift_low_latency/microshift-low-latency.adoc#microshift-low-latency-config-yaml_microshift-low-latency[Configuration kubelet parameters and values in {microshift-short}]
+* xref:../../microshift_configuring/microshift-feature-gates.adoc#microshift-feature-gates-using_microshift-feature-gates[Using feature gates for {microshift-short}]
+
 //RHEL TuneD
 include::modules/microshift-low-latency-tuned-conc.adoc[leveloffset=+1]
 

modules/microshift-low-latency-llc.adoc

@@ -0,0 +1,45 @@
+// Module included in the following assemblies:
+//
+// microshift_configuring/microshift_low_latency/microshift-low-latency.adoc
+
+:_mod-docs-content-type: PROCEDURE
+[id="microshift-low-latency-llc-enable_{context}"]
+= Enabling last-level cache locality in {microshift-short}
+
+[role="_abstract"]
+You can align workloads with CPU cores that share the same last-level cache (LLC) to improve performance for latency-sensitive applications. To apply this alignment, enable the Kubernetes CPU Manager option `prefer-align-cpus-by-uncorecache` in {microshift}.
+
+:FeatureName: Last-level cache (LLC) locality
+include::snippets/technology-preview.adoc[]
+:FeatureName!:
+
+[WARNING]
+====
+This feature is part of a feature gate. After you enable feature gates, you cannot disable them or update {microshift-short}, and your cluster can become unstable or lose data. Enable feature gates only in non-production environments.
+====
+
+.Procedure
+
+. Add the following content to `/etc/microshift/config.yaml`. If you already have a `kubelet` section from the earlier section, merge the `cpuManagerPolicyOptions` entry and ensure the feature gate is present.
++
+[source,yaml]
+----
+apiServer:
+  featureGates:
+    featureSet: "CustomNoUpgrade"
+    customNoUpgrade:
+      enabled:
+      - "CPUManagerPolicyBetaOptions"
+kubelet:
+  reservedSystemCPUs: "0"
+  cpuManagerPolicy: static
+  cpuManagerPolicyOptions:
+    prefer-align-cpus-by-uncorecache: "true"
+----
+
+. To apply the configuration, restart {microshift-short} by running the following command:
++
+[source,terminal,subs="+quotes"]
+----
+$ sudo systemctl restart microshift
+----