Bring your towel and join one of the fastest growing data communities. Welcome to our second-generation open source orchestration platform, a completely rethought approach to dataflow automation.

Prefect Community

Hi everyone. I am running into an issue where a task is failing due to heartbeat. I have a master flow that kicks off another flow with the `create_flow_run` task. The child flow takes over 3 hours and completed successfully. However, the parent flow's task failed with `No heartbeat detected from the remote task; marking the run as failed.` I am using Prefect Cloud.

Please see thread for the code I am using to run the child flow. Thanks!

Untitled.py

Are you waiting for the child flow run to finish?

Yes. There is another task that depends on this one.

No. Here is what I have now. The first call to `run_ml_flow` is the 3h process that is dying.

```    ml_model_train_result = run_ml_flow(
        parameters=flow_parameters(
            script_path="projects/nte_optimization/train_main_remote_submit.py",
            checkout_branch=ml_repo_branch,
        ),
        name="train_main_remote_submit",
        environment=flow_environment(iterations=nte_iterations),
    )
    ml_model_train_result.set_upstream(ml_model_prep_result)

    ml_model_score_result = run_ml_flow(
        parameters=flow_parameters(
            script_path="projects/nte_optimization/scoring.py",
            checkout_branch=ml_repo_branch,
        ),
        name="scoring",
    )
    ml_model_score_result.set_upstream(ml_model_train_result)```
Note that when the child flow takes less time to finish (for example a 20 min task) the parent flow works as expected. The issue seems to be related to the child flow taking a long time.

Can you try doing <https://docs.prefect.io/orchestration/concepts/services.html#heartbeat-configuration|this> . Set the heartbeat to “thread” instead of the default “process”

Ok. I'll give it a try and report back in a few hours :slightly_smiling_face: Thanks Kevin.

Kevin, in the meantime, how can I change the name of the tasks above if both use `run_ml_flow`? I an setting the run_name which helps identify the child flow runs, but both tasks show the same name `run_ml_flow` on Prefect Cloud.

```    flow_run_id = create_flow_run(
        flow_name="flow_to_start",
        project_name="PROJECT_NAME",
        task_args={"name": "your custom name"},
    )```

No rush, but really wanna hear if this worked <@U012CK03GBA>

Hi Kevin. I completed one run. It 5 hours. It did not error. I will run it nightly for a few days to see if it happens. Thanks for your help!