Increase the appropriate resource limits for pods after determining if a pod is being CPU throttled or OOMKilled.
Return Kubernetes pods to a healthy state with resources available.
Determine the current limits of a pod.
ncn-w001# kubectl get po -n services POD_ID -o yaml
Look for the following section returned in the output:
resources:
limits:
cpu: "2"
memory: 2Gi
requests:
cpu: 10m
memory: 64Mi
Determine which Kubernetes entity (etcdcluster, deployment, statefulset, etc) is creating the pod.
The Kubernetes entity can be found with either of the following options:
Find the Kubernetes entity and grep for the pod in question.
In the following example, replace hbtd-etcd with the pod being used.
ncn-w001# kubectl get deployment,statefulset,etcdcluster,postgresql,daemonsets -A | grep hbtd-etcd
Example output:
services etcdcluster.etcd.database.coreos.com/cray-hbtd-etcd 32d
Describe the pod and look in the Labels section.
This section is helpful for tracking down which entity is creating the pod.
ncn-w001# kubectl describe pod -n services POD_ID
Excerpt from example output:
Labels: app=etcd
etcd_cluster=cray-hbtd-etcd
etcd_node=cray-hbtd-etcd-8r2scmpb58
Edit the entity.
In the example below, be sure to replace ENTITY_TYPE and ENTITY_NAME with the values determined in
the previous step (in the example output for the following step, these would be etcdcluster and
cray-hbtd-etcd, respectively).
ncn-w001# kubectl edit ENTITY_TYPE -n services ENTITY_NAME
Increase the resource limits for the pod.
resources: {}
Replace the text above with the following section, increasing the limits values:
resources:
limits:
cpu: "4"
memory: 8Gi
requests:
cpu: 10m
memory: 64Mi
Run a rolling restart of the pods.
ncn-w001# kubectl get po -n services | grep ENTITY_NAME
Example output:
cray-hbtd-etcd-8r2scmpb58 1/1 Running 0 5d11h
cray-hbtd-etcd-qvz4zzjzw2 1/1 Running 0 5d11h
cray-hbtd-etcd-vzjzmbn6nr 1/1 Running 0 5d11h
Kill the pods off one by one.
Wait for each replacement pod to come up and be in a Running state before proceeding to the next pod.
ncn-w001# kubectl -n services delete pod POD_ID
Verify that all pods are now Running with a more recent age.
ncn-w001# kubectl get po -n services | grep ENTITY_NAME
Example output:
cray-hbtd-etcd-8r2scmpb58 1/1 Running 0 12s
cray-hbtd-etcd-qvz4zzjzw2 1/1 Running 0 32s
cray-hbtd-etcd-vzjzmbn6nr 1/1 Running 0 98s