Reference library

Concurrency & performance

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

3 matches
Concurrency & performance medium

Build a Python Performance Profiler That Generates Readable Reports

Use cProfile and pstats to profile Python functions and print a sorted performance report showing the top time-consuming calls.

profiling cprofile pstats
Python
import cProfile
import pstats
import io
from pathlib import Path

def slow_function():
    total = 0
    for i in range(500_000):
        total += i ** 2
    return total

def fast_function():
    total = sum(i * i for i in range(500_000))
    return total

def profile_functions():
    profiler = cProfile.Profile()
  …
44 0 Open
Concurrency & performance medium

How to Build a Producer-Consumer Pattern with asyncio.Queue in Python

This code implements a classic producer-consumer pattern using asyncio.Queue to coordinate one producer task that generates items and two consumer tasks that process them concurrently, with a sentinel value to signal completion.

asyncio queue concurrency
Python
import asyncio
import random


async def producer(queue, item_count):
    for i in range(item_count):
        item = random.randint(1, 100)
        await queue.put(item)
        print(f"Produced: {item}")
        await asyncio.sleep(0.1)
    await queue.put(None)  # Sentinel to signal end


async def consumer(queue, n…
15 0 Open
Concurrency & performance medium

How to Use a Weakref Cache to Avoid Memory Leaks in Python

This code demonstrates building a value cache with weakref.WeakValueDictionary so objects can be garbage collected when no longer referenced, preventing memory leaks.

weakref caching memory
Python
import weakref
import gc


class ExpensiveObject:
    def __init__(self, name):
        self.name = name

    def __repr__(self):
        return f"ExpensiveObject('{self.name}')"


class ObjectCache:
    def __init__(self):
        self._cache = weakref.WeakValueDictionary()

    def get_or_create(self, name):
       …
13 0 Open

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Concurrency & performance — Python code examples

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This page collects concurrency & performance snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.

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Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.