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in prefect 1, is there a way to disable parallel execution of tasks? i'm doing `create_flow_run.map()` and it's spinning up too many threads. im running out of threads/memory. i would rather execute sequentially

Can't you specify a `SequentialTaskRunner` in your flow ? Or is it just in prefect2 :thinking_face:

doesn't seem to be the case? <https://docs-v1.prefect.io/orchestration/flow_config/executors.html#executors>

```from prefect.executors import LocalExecutor


with Flow(
    'my_flow',
    executor=LocalExecutor(),
):
    ...```

Maybe you can try `executor = LocalDaskExecutor(num_workers=1)`

thank you <@U02989KQDQT> and <@U01HBGEDLNA>.i will give them both a shot!

<@U02989KQDQT> we are not explicitly setting an executor, so it seems we are running with `LocalExecutor` by default?

Not 100% sure what the default would be, as it varies by execution environment
```- executor (prefect.executors.Executor, optional): The executor that the flow
           should use. If `None`, the default executor configured in the runtime environment
           will be used.```

Looking more closely at your example, it seems like you are running multiple flows at once, is that the case?

yeah, i am running a series of dependent flows: <https://docs-v1.prefect.io/core/idioms/flow-to-flow>

I have a similar code like:
```from prefect import task, Flow, Parameter, unmapped
from prefect.executors import LocalDaskExecutor
from prefect.tasks.prefect import create_flow_run, wait_for_flow_run

executor = LocalDaskExecutor(num_workers=1)

with Flow("you_flow_orchestrator_name", executor=executor, ) as flow:
	
	# run_parameters takes a list of dicts of parameters to run
	load_flow = create_flow_run.map(flow_name=unmapped("slave_flow"), project_name=unmapped("slave_project"), parameters=any_list_of_dict_param)

	# Wait for workers
	wait_for_flow_run = wait_for_flow_run.map(flow_run_id=load_flow)```
I hope works for you!

<@U01HBGEDLNA> thank you! :thank-you:  checking that out