Reference library

Concurrency & performance

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

3 matches
Concurrency & performance medium

How to Parse JSON Files in Parallel with Python ThreadPoolExecutor

Load and transform JSON records from multiple files concurrently using ThreadPoolExecutor for faster I/O-bound parsing.

threadpool json concurrency
Python
import time
from concurrent.futures import ThreadPoolExecutor
import json

def load_json_file(path):
    with open(path, 'r') as f:
        return json.load(f)

def transform_record(record):
    record['full_name'] = f"{record.pop('first_name', '')} {record.pop('last_name', '')}".strip()
    record['score'] = int(reco…
17 0 Open
Concurrency & performance medium

How to Share a Queue Between Processes in Python

Use multiprocessing.Queue to pass work from a producer process to multiple consumer processes, coordinating with a sentinel stop message.

multiprocessing queue concurrency
Python
import multiprocessing
import time


def producer(queue, items):
    for item in items:
        queue.put(item)
        time.sleep(0.1)
    queue.put("STOP")


def consumer(queue, name):
    while True:
        item = queue.get()
        if item == "STOP":
            break
        print(f"{name} processed: {item}")

…
14 0 Open
Concurrency & performance medium

How to Use asyncio Lock to Protect a Shared Counter in Python

This code demonstrates how to use an asyncio.Lock to safely increment a shared counter from multiple concurrent coroutines.

asyncio lock concurrency
Python
import asyncio

async def increment(counter, lock, increments):
    for _ in range(increments):
        async with lock:
            counter[0] += 1

async def main():
    counter = [0]
    lock = asyncio.Lock()
    tasks = [
        increment(counter, lock, 1000)
        for _ in range(5)
    ]
    await asyncio.gath…
16 0 Open

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