Spreading jupyter-XXXX pods in the cluster

JupyterHub Zero to JupyterHub on Kubernetes
1

Hi all, I deployed JH in K8s cluster.
I’m looking for a way to spread the pods of new users in different nodes of the cluster, rather that in the same node as the previous pod.

Thanks!

2

Did you change any related configuration settings?
For instance, we only maintain a static amount of nodes, so we disabled the user scheduler and user placeholder.

Maybe you can share your node setup and the Helm chart configuration?

1 Like
3

I believe this is what pod anti-affinity is for. So I believe this config would spread user pods out across nodes:

    scheduling:
      userScheduler:
        enabled: false
    singleuser:
      extraPodAntiAffinity:
        preferred:
          - podAffinityTerm:
              labelSelector:
                matchLabels:
                  component: singleuser-server
            weight: 10

But just disabling the user scheduler might be enough:

scheduling:
  userScheduler:
    enabled: false

The user scheduler packs user pods next to each other to maximize the effectiveness of scale-down in autoscaling clusters. If you don’t have an autoscaling cluster, then it can be disabled without any expected negative impacts, I think.