On Docker, --cpuset-cpus=0 will pin the container to the first core.
K8s: https://kubernetes.io/docs/tasks/administer-cluster/cpu-mana...
CPU affinity and pinning is something I think you should be able to achieve without too much hassle.
Just let the CPU scheduler do its job. Unless you know better, in which case, by all means go ahead and allocate computational resources manually. I don't see a way to make that a sensible default, though.
Neat, I didn't know it was a single flag in Docker.
The k8s method you linked definitely has some caveats as it doesn't allow this scheduling at the pod level, and requires quite a bit of fiddling to get working (atleast on GKE). This isn't even available if you use a fully managed setup like autopilot.
Maybe my expectations just aren't realistic but "easy" to me would mean I put the affinity right next to my CPU request in the podSpec :/