Downward API shows incorrect values for cpu.request/cpu.limit when exposed through volumeMount #64579
Description
Is this a BUG REPORT or FEATURE REQUEST?:
/kind bug
What happened:
Using the Downward API as a disk volume, I am getting incorrect values for cpu.request and cpu.limit.
What you expected to happen:
I expect to see the same values for cpu.limit and cpu.request that I see when I run kubectl describe pod <...>.
How to reproduce it (as minimally and precisely as possible):
Create a pod with the Downward API exposed through a volumeMount:
apiVersion: v1
kind: ReplicationController
metadata:
name: nginx
spec:
replicas: 2
selector:
app: nginx
template:
metadata:
name: nginx
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
resources:
requests:
cpu: "100m"
memory: "15M"
limits:
cpu: "500m"
memory: "100M"
volumeMounts:
- mountPath: /etc/podinfo
name: podinfo
volumes:
- name: podinfo
downwardAPI:
items:
- path: "cpu_limit"
resourceFieldRef:
containerName: ssl-proxy
resource: limits.cpu
- path: "cpu_request"
resourceFieldRef:
containerName: ssl-proxy
resource: requests.cpu
- path: "mem_limit"
resourceFieldRef:
containerName: ssl-proxy
resource: limits.memory
- path: "mem_request"
resourceFieldRef:
containerName: ssl-proxy
resource: requests.memory
kubectl exec -t -i <pod> bash to get a shell and then:
# cd /etc/podinfo
# for i in *; do echo "$i -> $(cat $i)"; done
cpu_limit -> 1
cpu_request -> 1
mem_limit -> 500000000
mem_request -> 100000000
Observe that cpu_limit and cpu_request are both 1.
Now, adjust the limit and request:
kubectl set resources replicationcontroller nginx --requests=cpu=900m --limits=cpu=1400m
Wait for your pod to be rebuilt and exec a new bash shell onto it.
# cd /etc/podinfo
# for i in *; do echo "$i -> $(cat $i)"; done
cpu_limit -> 2
cpu_request -> 1
mem_limit -> 500000000
mem_request -> 100000000
Notice how the values appear to be rounded up. They should probably be displayed as millicores (int).
Anything else we need to know?:
Environment:
- Kubernetes version (use
kubectl version):
Client Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.2", GitCommit:"81753b10df112992bf51bbc2c2f85208aad78335", GitTreeState:"clean", BuildDate:"2018-04-27T09:22:21Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.3", GitCommit:"2bba0127d85d5a46ab4b778548be28623b32d0b0", GitTreeState:"clean", BuildDate:"2018-05-21T09:05:37Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}
-
Cloud provider or hardware configuration:
AWS / kops / t2.xlarge nodes -
OS (e.g. from /etc/os-release):
Container Linux by CoreOS stable (1745.4.0) -
Kernel (e.g.
uname -a):Linux ip-10-25-50-145.ec2.internal 4.14.42-coreos #1 SMP Thu May 24 21:10:56 UTC 2018 x86_64 Intel(R) Xeon(R) CPU E5-2676 v3 @ 2.40GHz GenuineIntel GNU/Linux -
Install tools:
-
Others: