A memoized steps hit, the following nodes not displayed in the UI

[zjgemi]

Summary

When a memoized step with steps template is hit by a ConfigMap record, the nodes following this step are not displayed in the UI (despite they run expectedly). The behavior might result from that the memoized step has no children.

Diagnostics

The smallest workflow that reproduces the bug looks like

apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: memoized-bug-
spec:
  entrypoint: main
  templates:
  - name: main
    steps:
    - - name: hello-steps
        template: memoized
    - - name: whatever
        template: hello

  - name: memoized
    outputs:
      parameters:
      - name: msg
        valueFrom:
          parameter: "{{steps.hello-step.outputs.result}}"
    steps:
    - - name: hello-step
        template: hello
    memoize:
      key: "memoized-bug-steps-0"
      cache:
        configMap:
          name: my-config

  - name: hello
    container:
      image: alpine:latest
      command: [sh, -c]
      args: ["echo Hello"]

When the workflow is submitted for the first time, the step hello-steps is stored in the ConfigMap. And in the UI, the workflow looks like

Everything is OK. But when the workflow is submitted for the second time, the step hello-steps is loaded from the ConfigMap, the following step whatever is not displayed in the UI

In the detail of the second workflow

$ argo get memoized-bug-nmvgq -n argo -o yaml
...
    memoized-bug-nmvgq-667942788:
      boundaryID: memoized-bug-nmvgq
      displayName: hello-steps
      finishedAt: "2022-02-13T05:32:52Z"
      id: memoized-bug-nmvgq-667942788
      memoizationStatus:
        cacheName: my-config
        hit: true
        key: memoized-bug-steps-0
      name: memoized-bug-nmvgq[0].hello-steps
      outputs:
        parameters:
        - name: msg
          value: Hello
      phase: Succeeded
      startedAt: "2022-02-13T05:32:52Z"
      templateName: memoized
      templateScope: local/memoized-bug-nmvgq
      type: Steps
...
    memoized-bug-nmvgq-2677016171:
      boundaryID: memoized-bug-nmvgq
      displayName: whatever
      finishedAt: "2022-02-13T05:33:05Z"
      hostNodeName: minikube
      id: memoized-bug-nmvgq-2677016171
      name: memoized-bug-nmvgq[1].whatever
      outputs:
        artifacts:
        - name: main-logs
          s3:
            key: memoized-bug-nmvgq/memoized-bug-nmvgq-2677016171/main.log
        exitCode: "0"
      phase: Succeeded
      progress: 1/1
      resourcesDuration:
        cpu: 4
        memory: 2
      startedAt: "2022-02-13T05:32:52Z"
      templateName: hello
      templateScope: local/memoized-bug-nmvgq
      type: Pod

The step hello-steps does not have children which may cause the step whatever not displayed in the UI, despite the step whatever succeeded.

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[sarabala1979]

@zjgemi memoization is only storing the node status of a particular step/task, not an original template. I don't think we can get memoization templates.
one workaround: instead of configuring memoization on definition templates like steps/dag, you can configure memoization on execution templates like container, script, etc. It will give the same output.

[zjgemi]

@zjgemi memoization is only storing the node status of a particular step/task, not an original template. I don't think we can get memoization templates.
one workaround: instead of configuring memoization on definition templates like steps/dag, you can configure memoization on execution templates like container, script, etc. It will give the same output.

I understand the workaround. Thanks a lot.