Yes, there are several ways to run child flows concurrently in Prefect. Here's how you can do it: 1. Using `submit()`:

python
from prefect import flow

@flow
def child_flow(x):
    return x * 2

@flow
def parent_flow():
    # Submit multiple child flows to run concurrently
    futures = [
        child_flow.submit(i) for i in range(5)
    ]
    
    # Wait for all results
    results = [future.result() for future in futures]
    return results

2. Using

asyncio

with async flows:

python
from prefect import flow
import asyncio

@flow
async def async_child_flow(x):
    return x * 2

@flow
async def async_parent_flow():
    # Run child flows concurrently
    results = await asyncio.gather(
        *[async_child_flow(i) for i in range(5)]
    )
    return results

Key points to remember: - The

submit()

method returns a future object that you can use to get results later - Async flows provide native Python async/await syntax for concurrent execution - Child flows inherit the same deployment context as their parent flow - Concurrency limits can be managed through work pools and work queues if needed For more details on flow orchestration and concurrency patterns, you can refer to: - Workflow Design Patterns - Flows Documentation - Tag-based Concurrency Limits Would you like me to elaborate on any particular aspect of concurrent flow execution?

I apologize for my previous response - you're right to point out the error. Let me correct this: For true concurrent execution of flows, you'll want to use one of these approaches: 1. Using Tasks with a Task Runner:

python
from prefect import flow, task
from prefect.task_runners import ConcurrentTaskRunner

@task
def run_flow_as_task(x):
    # Your flow logic here
    return x * 2

@flow(task_runner=ConcurrentTaskRunner())
def parent_flow():
    futures = [run_flow_as_task.submit(i) for i in range(5)]
    results = [future.result() for future in futures]
    return results

2. Using Deployments: If you need true parallel flow execution, you should create separate deployments for your flows and trigger them programmatically:

python
from prefect import flow
from prefect.client import get_client

@flow
async def trigger_parallel_flows():
    async with get_client() as client:
        flow_runs = []
        for i in range(5):
            flow_run = await client.create_flow_run(
                deployment_id="your-deployment-id",
                parameters={"x": i}
            )
            flow_runs.append(flow_run)
    return flow_runs

The key differences are: - Subflows (child flows) run in the same process as the parent flow by default - For true parallelism, you need either: - Tasks with a concurrent task runner - Separate deployments that can run independently - Deployments can run on different workers/machines, offering true parallel execution For more details on concurrent execution, you can refer to: - Running Work Concurrently - Workflow Design Patterns Would you like me to elaborate on either of these approaches?