A Practical Guide to Kubernetes/

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Allocating Excessive Resources

Allocating Excessive Resources

Explore what happens when we allocate excessive resources than required by an application.

We'll cover the following...

Allocating excessive memory

Let’s explore another possible situation through yet another updated definition go-demo-2-insuf-node. Just as before, the change is only in the resources of the go-demo-2-db Deployment.

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apiVersion: apps/v1
kind: Deployment
metadata:
  name: go-demo-2-db
spec:
  ...
  template:
    ...
    spec:
      containers:
      - name: db
        image: mongo:3.3
        resources:
          limits:
            memory: 8Gi
            cpu: 0.5
          requests:
            memory: 12Gi
            cpu: 0.3

This time we specify that the requested memory is twice as much as the total memory of the node (6GB). The memory limit is even higher.

Applying the definition

Let’s apply the change and observe what happens.

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kubectl apply \
    -f go-demo-2-insuf-node.yml \
    --record
kubectl get pods

The output of the latter command is as follows:

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NAME              READY STATUS  RESTARTS AGE
go-demo-2-api-... 1/1   Running 0        8m
go-demo-2-api-... 1/1   Running 0        8m
go-demo-2-api-... 1/1   Running 0        9m
go-demo-2-db-...  0/1   Pending 0        13s

This time, the status of the Pod ...