Rebuilding specific version Kubernetes

Here is an issue with opening Linux kernel memory, so the customers need to rebuild specific version of kubelet.

Building

Checking out to the specific version of Kubernetes

# For example, the target version is v1.20.15
git checkout v1.20.15

Executing building command

KUBE_BUILD_PLARFORMS support different OS/architecture like OSX and GNU/Linux

# For example
=linux/arm64
=linux/amd64

The complete command can be

KUBE_GIT_VERSION=v1.20.15 ./build/run.sh make kubelet KUBE_BUILD_PLATFORMS=linux/arm64 GOFLAGS="-tags=nokmem"

And we can find the binary under the project root folder was named _output

Testing

The command for checking for all the containers, if mem.txt is empty, kernel memory feature was already closed.

find /sys/fs/cgroup/memory/kubepods/ -name memory.kmem.slabinfo | xargs cat > /tmp/mem.txt

The command for checking specific container

cat /sys/fs/cgroup/memory/kubepods/burstable/pod<pod-uid>/<container-id>/memory.kmem.slabinfo

Checking memory.kmem.slabinfo that it does not contains Input/output error

cat: memory.kmem.slabinfo: Input/output error

Reference:

https://github.com/kubernetes/kubernetes/issues/61937