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Hi - I have a flow that runs in k8s and uses the SequentialTaskRunner to call about 3k tasks - 90% of the time the flow fails with the error following in the thread. Any ideas on where to start debugging this issue? 10% of the time the flow completes successfully.

```Encountered exception during execution:
Traceback (most recent call last):
  File "/usr/local/lib/python3.10/asyncio/runners.py", line 44, in run
    return loop.run_until_complete(main)
  File "/usr/local/lib/python3.10/asyncio/base_events.py", line 636, in run_until_complete
    self.run_forever()
  File "/usr/local/lib/python3.10/asyncio/base_events.py", line 603, in run_forever
    self._run_once()
  File "/usr/local/lib/python3.10/asyncio/base_events.py", line 1871, in _run_once
    event_list = self._selector.select(timeout)
  File "/usr/local/lib/python3.10/selectors.py", line 469, in select
    fd_event_list = self._selector.poll(timeout, max_ev)
  File "/usr/local/lib/python3.10/site-packages/prefect/engine.py", line 1670, in cancel_flow_run
    raise TerminationSignal(signal=signal.SIGTERM)
prefect.exceptions.TerminationSignal

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/prefect/engine.py", line 665, in orchestrate_flow_run
    result = await run_sync(flow_call)
  File "/usr/local/lib/python3.10/site-packages/prefect/utilities/asyncutils.py", line 165, in run_sync_in_interruptible_worker_thread
    assert result is not NotSet
AssertionError```

image.png

Just seems to be too random when it fails, no commonality with a certain problematic record or running time. For me it points to a prefect issue rather than anything in the flow which is not changing at all.

I dont have big brains but Id start with the following I guess.
1. Are the tasks in a subflow?
2. What do the tasks return? I am thinking maybe memory issues?
3. Have you tried running in a "Process agent" on your local machine?

4. Whats the logs in the kubernetes agent pods?

Logs from the agent above, no subflows, pods do not OOM, tasks are marked with cache_result_in_memory=False

it runs fine locally when I use vscode to run the flow

Where is the database? Have you set up a postgres database, or is prefect using an sqlite database?

Ahhh ok. My guess was going to be sqlite was not fit for that many tasks

going to upgrade the flow &amp; agent to 2.11.2 and try again but this has been like this for weeks