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Concurrency & performance

asyncio, threading, multiprocessing, and profiling-friendly performance patterns.

3 matches

How to Run an Async Main with asyncio.run in Python

Show the canonical entry point for an asyncio program: define an async main, then launch it with asyncio.run.

import asyncio


async def main():
    print("Hello from async main")
    await asyncio.sleep(0.1)
    print("Done")


if __name__ == "__main__":
    asyncio.run(main())

16 0 Open

Concurrency & performance easy

How to Use uvloop Faster Event Loop

Install uvloop at startup to replace asyncio's default event loop with a faster libuv-based one, with a graceful fallback when it's unavailable.

uvloop asyncio event-loop

Python

import asyncio
try:
    import uvloop
    uvloop.install()
    USING_UVLOOP = True
except ImportError:
    USING_UVLOOP = False


async def fetch_data(index):
    await asyncio.sleep(0.01)
    return f"data-{index}"


async def main():
    tasks = [fetch_data(i) for i in range(10)]
    results = await asyncio.gather(*…

14 0 Open

Concurrency & performance easy

Run Background Tasks with asyncio.create_task in Python

Create background tasks in an asyncio event loop with asyncio.create_task and run them concurrently using asyncio.gather.

asyncio async concurrency

Python

import asyncio
import time

async def background_worker(name, duration):
    """Simulates a long-running background task."""
    print(f"{name} started at t={time.monotonic():.1f}")
    await asyncio.sleep(duration)
    print(f"{name} finished at t={time.monotonic():.1f}")

async def main():
    print(f"Main starting …

13 0 Open

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