Disable Transparent Huge Pages from Kubernetes

Yes, with init-containers it's quite straightforward:

apiVersion: v1kind: Podmetadata:  name: thp-testspec:  restartPolicy: Never  terminationGracePeriodSeconds: 1  volumes:    - name: host-sys      hostPath:        path: /sys  initContainers:    - name: disable-thp      image: busybox      volumeMounts:        - name: host-sys          mountPath: /host-sys      command: ["sh", "-c", "echo never >/host-sys/kernel/mm/transparent_hugepage/enabled"]  containers:    - name: busybox      image: busybox      command: ["cat", "/sys/kernel/mm/transparent_hugepage/enabled"]

Demo (notice that this is a system wide setting):

$ ssh THATNODE cat /sys/kernel/mm/transparent_hugepage/enabledalways [madvise] never$ kubectl create -f thp-test.yamlpod "thp-test" created$ kubectl logs thp-testalways madvise [never]$ kubectl delete pod thp-testpod "thp-test" deleted$ ssh THATNODE cat /sys/kernel/mm/transparent_hugepage/enabledalways madvise [never]

Ay,

I don't know if what I did is a good idea but we needed to deactivate THP on all our K8S VMs for all our apps. So I used a DaemonSet instead of adding an init-container to all our stacks :

apiVersion: apps/v1kind: DaemonSetmetadata:  name: thp-disable  namespace: kube-systemspec:  selector:    matchLabels:      name: thp-disable  template:    metadata:      labels:        name: thp-disable    spec:      restartPolicy: Always      terminationGracePeriodSeconds: 1      volumes:        - name: host-sys          hostPath:            path: /sys      initContainers:        - name: disable-thp          image: busybox          volumeMounts:            - name: host-sys              mountPath: /host-sys          command: ["sh", "-c", "echo never >/host-sys/kernel/mm/transparent_hugepage/enabled"]      containers:        - name: busybox          image: busybox          command: ["watch", "-n", "600", "cat", "/sys/kernel/mm/transparent_hugepage/enabled"]

I think it's a little dirty but it works.