Add playbook to set SMT on worker nodes

Author: kishen-v

kubetest2-tf/data/k8s-ansible/group_vars/all

@@ -16,6 +16,11 @@ update_os_packages: false
 # kubeconfig on the local machine where kubeconfig content will be copied from the remote machine
 kubeconfig_path: kubeconfig
 
+##### Node level SMT settings #####
+smt_config:
+  workers: 4
+  masters: 8
+
 ##### Runtime Configurations #####
 # cri-tools version
 critools_version: 1.29.0

kubetest2-tf/data/k8s-ansible/install-k8s-ha.yml

@@ -22,6 +22,18 @@
     - download-k8s
     - install-k8s
 
+- name: Set desired SMT levels on nodes
+  hosts:
+    - masters
+    - workers
+  tasks:
+    - name: Apply SMT configuration
+      include_role:
+        name: set-smt
+      vars:
+        smt_level: "{{ item.value }}"
+      loop: "{{ smt_config | dict2items }}"
+
 - name: Install networking - calico
   hosts: masters
   roles:

kubetest2-tf/data/k8s-ansible/roles/set-smt/tasks/main.yml

@@ -0,0 +1,20 @@
+- name: Resolve Kubernetes node name from inventory IP
+  shell: |
+    kubectl get nodes -o jsonpath="{range .items[*]}{.metadata.name} {.status.addresses[?(@.type=='InternalIP')].address}{'\n'}{end}" \
+    --kubeconfig {{ kubeconfig_path }} | grep {{ inventory_hostname }} | awk '{print $1}'
+  register: node_name
+  delegate_to: "{{ groups['masters'][0] }}"
+
+- name: Add SMT level label to node
+  shell: |
+    kubectl label node/{{ node_name.stdout }} feature.node.kubernetes.io/ppc64le.smtlevel="{{ smt_level }}" --overwrite
+  delegate_to: "{{ groups['masters'][0] }}"
+  when: inventory_hostname in groups[item.key]
+
+- name: Set SMT level
+  shell: ppc64_cpu --smt={{ smt_level }}
+  when: inventory_hostname in groups[item.key]
+
+- name: Restart kubelet to update the node's capacity at the cluster level
+  shell: systemctl restart kubelet
+  when: inventory_hostname in groups[item.key]