kubernetes: Container Termination Discrepancy for Exit Code 137

In the documentation here it shows a pod using too much memory and is promptly killed. When this happens it shows the error reason as “OOM” and error code as 137 in the docs. When I go through similar steps myself, the termination reason is just “Error”, though I do still get the 137 error code. Is there a reason this was changed? OOM is very clear on what happened while “Error” can send people down a wild chase trying to figure out what happened to their pod - hence me filing this issue.

For reference the script ran in my docker image just eats memory until it the container gets killed.

$kubectl version
Client Version: version.Info{Major:"1", Minor:"1", GitVersion:"v1.1.1", GitCommit:"92635e23dfafb2ddc828c8ac6c03c7a7205a84d8", GitTreeState:"clean"}
Server Version: version.Info{Major:"1", Minor:"1", GitVersion:"v1.1.3", GitCommit:"6a81b50c7e97bbe0ade075de55ab4fa34f049dc2", GitTreeState:"clean"}

$ kubectl get pod -o json  memtest
{
    "kind": "Pod",
    "apiVersion": "v1",
    "metadata": {
        "name": "memtest",
        "namespace": "default",
        "selfLink": "/api/v1/namespaces/default/pods/memtest",
        "uid": "c480d1ba-bec2-11e5-ad45-062d2421a4bd",
        "resourceVersion": "21949421",
        "creationTimestamp": "2016-01-19T15:39:03Z"
    },
    "spec": {
        "containers": [
            {
                "name": "memtest",
                "image": "nyxcharon/docker-stress:latest",
                "args": [
                    "python",
                    "/scripts/mem-fill"
                ],
                "resources": {
                    "limits": {
                        "memory": "10M"
                    },
                    "requests": {
                        "memory": "10M"
                    }
                },
                "terminationMessagePath": "/dev/termination-log",
                "imagePullPolicy": "Always"
            }
        ],
        "restartPolicy": "Never",
        "terminationGracePeriodSeconds": 30,
        "dnsPolicy": "ClusterFirst",
        "nodeName": "<IP removed>"
    },
    "status": {
        "phase": "Failed",
        "conditions": [
            {
                "type": "Ready",
                "status": "False",
                "lastProbeTime": null,
                "lastTransitionTime": null
            }
        ],
        "hostIP": "<IP Removed>",
        "startTime": "2016-01-19T15:39:03Z",
        "containerStatuses": [
            {
                "name": "memtest",
                "state": {
                    "terminated": {
                        "exitCode": 137,
                        "reason": "Error",
                        "startedAt": "2016-01-19T15:39:15Z",
                        "finishedAt": "2016-01-19T15:39:16Z",
                        "containerID": "docker://3dd77f77dfd6e715c8792c625f388e0b31cbd36ccdb4a11dafbb6d381bf83943"
                    }
                },
                "lastState": {},
                "ready": false,
                "restartCount": 0,
                "image": "nyxcharon/docker-stress:latest",
                "imageID": "docker://bacbb71b34e92ed2074621d86b10ec15a856f5918537c4d75b6f16925b5b93e7",
                "containerID": "docker://3dd77f77dfd6e715c8792c625f388e0b31cbd36ccdb4a11dafbb6d381bf83943"
            }
        ]
    }
}

$ kubectl describe pod memtest
Name:               memtest
Namespace:          default
Image(s):           nyxcharon/docker-stress:latest
Node:               <IP removed>
Start Time:         Tue, 19 Jan 2016 10:39:03 -0500
Labels:             <none>
Status:             Failed
Reason:
Message:
IP:
Replication Controllers:    <none>
Containers:
  memtest:
    Container ID:   docker://3dd77f77dfd6e715c8792c625f388e0b31cbd36ccdb4a11dafbb6d381bf83943
    Image:      nyxcharon/docker-stress:latest
    Image ID:       docker://bacbb71b34e92ed2074621d86b10ec15a856f5918537c4d75b6f16925b5b93e7
    QoS Tier:
      memory:   Guaranteed
    Limits:
      memory:   10M
    Requests:
      memory:       10M
    State:      Terminated
      Reason:       Error
      Exit Code:    137
      Started:      Tue, 19 Jan 2016 10:39:15 -0500
      Finished:     Tue, 19 Jan 2016 10:39:16 -0500
    Ready:      False
    Restart Count:  0
    Environment Variables:
Conditions:
  Type      Status
  Ready     False
No volumes.
Events:
  FirstSeen LastSeen    Count   From                    SubobjectPath               Reason  Message
  ─────────   ────────    ───── ────                    ─────────────             ──────  ───────
  2m        2m      1   {kubelet <IP removed>}  implicitly required container POD   Pulled  Container image "gcr.io/google_containers/pause:0.8.0" already present on machine
  2m        2m      1   {scheduler }                                    Scheduled   Successfully assigned memtest to <IP removed>
  2m        2m      1   {kubelet <IP removed>}  implicitly required container POD   CreatedCreated with docker id 65a446677edd
  2m        2m      1   {kubelet <IP removed>}  spec.containers{memtest}        PullingPulling image "nyxcharon/docker-stress:latest"
  2m        2m      1   {kubelet <IP removed>}  implicitly required container POD   StartedStarted with docker id 65a446677edd
  2m        2m      1   {kubelet <IP removed>}  spec.containers{memtest}        Pulled  Successfully pulled image "nyxcharon/docker-stress:latest"
  2m        2m      1   {kubelet <IP removed>}  spec.containers{memtest}        CreatedCreated with docker id 3dd77f77dfd6
  2m        2m      1   {kubelet <IP removed>}  spec.containers{memtest}        StartedStarted with docker id 3dd77f77dfd6
  2m        2m      1   {kubelet <IP removed>}  implicitly required container POD   KillingKilling with docker id 65a446677edd

Here is the pod definition i’m using:

kind: Pod
apiVersion: v1
metadata:
  name: memtest
spec:
  containers:
  - name: memtest
    image: nyxcharon/docker-stress:latest
    args:
    - python
    - /scripts/mem-fill
    resources:
      limits:
        memory: 10M
  restartPolicy: Never