Hi Flyte team! I'm traying to use the papermill plugin on a Kubernetes cluster that uses Istio. For that, I've also installed the pod plugin (to deal with the sidecar issue). For regular python tasks, the _task_type_ changes to

sidecar

task and the pod can be terminated as expected using the pod plugin. However, when running a workflow with a notebook task for papermill, the _task_type_ changes to

nb-sidecar

. After that, the pod for this task can not be terminated and I don't know why. It seems like the same issue when we launch a workflow without the proper settings for pod plugin. A code snipet for the task:

def generate_por_spec_for_task():
    primary_container = V1Container(name="primary")
    pod_spec = V1PodSpec(containers=[primary_container])

    return pod_spec

nb = NotebookTask(
    name="simple-nb",
    task_config=Pod(pod_spec=generate_por_spec_for_task(), primary_container_name="primary"),
    notebook_path=os.path.join(
        pathlib.Path(file).parent.absolute(), "nb-simple.ipynb"
    ),
    inputs=kwtypes(v=float),
    outputs=kwtypes(square=float),
)

A log message in flytepropeller pod is the following:

{"json":{"exec_id":"ahkm5jd76h8l2gn46zt6","node":"n1","ns":"flyteexamples-development","res_ver":"209788243","routine":"worker-2","tasktype":"nb-sidecar","wf":"flyteexamples:development:flyte.workflows.simple.nb_to_python_wf"},"level":"warning","msg":"No plugin found for Handler-type [nb-sidecar], defaulting to [container]","ts":"2022-edited"}

Does anyone has insights about what could possibly going on?

Could you share your plugin config in the propeller config map?

Hi! Thanks for the quick response @glamorous-carpet-83516! The values are the same that you shared: flyte-propeller-config enabled_plugins.yaml

tasks:
  task-plugins:
    default-for-task-types:
      container: container
      container_array: k8s-array
      sidecar: sidecar
    enabled-plugins: 
      - container
      - sidecar
      - k8s-array

There is nothing specific for nb-task or papermill plugin...

cc @shy-holiday-15500 mind taking a look? did you run into same issue before

I haven't seen this issue in particular, but we also aren't running Istio (the only other things we have on the nodes with the nb task pods are daemon set pods). This "can not be terminated" behaviour only happens with notebook tasks right? "The task can not be terminated" -> You mean the underlying pod can't be deleted using kubectl etc.? Or you can't terminate the task's execution from the GUI?

Hi @shy-holiday-15500! Thanks for your time! Yes, this behavior is just for the notebook_task. Running it locally, the workflow is OK and gives the right outputs. However, running it on the cluster, the sidecar keeps running forever. From the GUI, the notebook_task status is "unknown" and I've to terminate the workflow from the GUI. I've added a regular python task (with the config_task for pod plugin) just before the notebook task in the same workflow to do some experiments. The regular python task is executed, after ending the task, kubernetes automatically terminate the pod for that task, as expected. The following task is the notebook_task, but when it is running, the task gets stuck and process is not finished. I've tried a naïve approach to edit the config map to map the `nb-sidecar`task as a

sidecar

task. It didn't work. But I think that it just don't work like that. I don't know how to change the default task to

sidecar

instead of

container

... Maybe worth trying that to see what happens...

Cool thanks for the description! I haven't touched the

sidecar

task type all that much, but presumably propeller must have some logic for those to tear down the sidecar that isn't getting used here. I suspect there is a bug here and we need to tweak something so that propeller uses a sidecar-aware plugin, and happy to help continue debugging, but will be slower since I'm new to this part of the code. I can think of an inelegant workaround if you need this quickly: you could use a plain python task and use the python papermill library in it to run your notebook.

Thanks! I'll try this workaround for now 🙂

@strong-oyster-56522 this seems like Flyte is unable To detect primary container exit. So k8s sidecar block pod termination and Flyte intervenes. But need to see why this did not work

okay. it works after I removed

nb-

from task type

Ya the task type is not useful

Thanks @freezing-airport-6809 and @glamorous-carpet-83516! I'll try some alternatives!

You don’t need alternatives. Kevin is putting in a change

Thank you all! 😀

@strong-oyster-56522 We’ve fixed it. Feel free to try it.

pip install git+<https://github.com/flyteorg/flytekit@papermill-bug>

https://github.com/flyteorg/flytekit/pull/1143