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Concurrency & performance

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

4 matches

How to Run Blocking Code in an Executor with asyncio in Python

This code runs blocking functions concurrently without stalling the event loop by offloading them to thread pool executors via asyncio.

asyncio executor concurrency

Python

import asyncio
import time


def blocking_task(name: str, duration: float) -> str:
    """Simulate a blocking operation."""
    time.sleep(duration)
    return f"Finished {name} after {duration}s"


async def main() -> None:
    loop = asyncio.get_running_loop()
    results = await asyncio.gather(
        loop.run_in_…

13 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

How to set a timeout with asyncio.wait_for in Python

Use asyncio.wait_for to bound an async function with a timeout, catching TimeoutError when it exceeds the limit.

asyncio timeout concurrency

Python

import asyncio

async def slow_task():
    await asyncio.sleep(3)
    return "finished"

async def main():
    try:
        result = await asyncio.wait_for(slow_task(), timeout=1)
        print(result)
    except asyncio.TimeoutError:
        print("Task timed out")

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

13 0 Open

Concurrency & performance easy

asyncio sleep cooperative scheduling demo in Python

This demo shows how asyncio.sleep yields control between concurrent tasks, letting multiple workers interleave their ticks.

asyncio concurrency scheduling

Python

import asyncio

async def worker(name, delay):
    for i in range(3):
        print(f"{name}: tick {i}")
        await asyncio.sleep(delay)
    return f"{name} done"

async def main():
    tasks = [
        asyncio.create_task(worker("A", 0.1)),
        asyncio.create_task(worker("B", 0.2)),
        asyncio.create_tas…

12 0 Open

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