Reference library

Concurrency & performance

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

4 matches

How to Signal asyncio Workers to Stop with an Event in Python

Use an asyncio.Event to coordinate graceful shutdown of multiple concurrent worker tasks in Python.

import asyncio
import random

async def worker(name, stop_event):
    while not stop_event.is_set():
        await asyncio.sleep(random.uniform(0.1, 0.5))
        print(f"Worker {name} processing...")
    print(f"Worker {name} stopped.")

async def main():
    stop_event = asyncio.Event()
    workers = [asyncio.create…

11 0 Open

Concurrency & performance easy

Synchronize Threads with a Barrier in Python

Demonstrates using threading.Barrier to synchronize multiple threads at phase boundaries, ensuring all workers wait for each other before proceeding.

threading synchronization barrier

Python

import threading
import time
from random import randint

def worker(barrier, worker_id):
    for phase in range(3):
        time.sleep(randint(1, 3))
        print(f"Worker {worker_id} finished phase {phase} at {time.time():.2f}")
        barrier.wait()
    print(f"Worker {worker_id}: all phases complete")

if __name_…

14 0 Open

Concurrency & performance medium

asyncio Condition wait notify pattern in Python

Coordinate coroutines with asyncio.Condition: workers wait for notifications and the main task notifies one or all of them.

asyncio concurrency synchronization

Python

import asyncio


async def worker(condition, name):
    async with condition:
        print(f"{name} waiting...")
        await condition.wait()
        print(f"{name} notified!")


async def main():
    condition = asyncio.Condition()
    tasks = [asyncio.create_task(worker(condition, f"worker-{i}")) for i in range(3…

14 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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