python / python/cpython

Issues in asyncio documentation section "A homemade asyncio.sleep"

Abierto
#143,727 6 comentarios 0 reacciones 1 asignado Ver en GitHub

@willingc ya está trabajando en esto.

Desde el 23/7/2026.

  • #143850 de @anordin95 — abierto
docs topic-asyncio
Lenguaje dominante
Python
Estrellas
77.2k
Forks
35.9k
Métricas de merge de PR
Métricas de PR pendientes

Descripción

Documentation

Link to section:
https://docs.python.org/3/howto/a-conceptual-overview-of-asyncio.html#a-homemade-asyncio-sleep

From my perspective, there are two issues in this section:

  1. Creating a task for the sleep call in main (await asyncio.create_task(async_sleep(3))) hides if the implementation actually cedes control to the event loop as desired or if it blocks it - an implementation using time.sleep(seconds) would also behave sane here. Therefore, I think it should be changed to await async_sleep(3).
  2. The implementation is said to mimick asyncio.sleep(), which can make readers think that this could actually be a usable replacement that behaves similarly. However, in one crucial aspect it behaves the opposite way: It causes 100% CPU usage on one core due to the busy waiting approach, which is opposed to how a sleep should behave. Two options I see:
  • Add something like: "Note: This implementation uses busy waiting and will consume 100% CPU on one core, unlike the real asyncio.sleep(). This implementation is purely meant for educational purposes to demonstrate futures and event loop interaction."
  • Add a synchronous time.sleep(0.001) or such right before await YieldToEventLoop() (in both example implementations) and explain (trade-off, sub-optimal workaround, will cause undesired CPU usage but significantly less than without).
Linked PRs
  • gh-143850

Guía de contribución

Abrir la guía de contribución

Primeros pasos

  1. Lee el issue completo y luego la guía de contribución del proyecto.
  2. Comenta en el issue que vas a ocuparte — evita que dos personas hagan lo mismo.
  3. Haz un fork del repositorio y trabaja en una rama.
  4. Abre un pull request que haga referencia al número del issue.

Evaluación

Este issue todavía no se ha evaluado.

Recibe los nuevos issues en tu correo

Un resumen breve de issues de GitHub para principiantes.