### Concurrence et Burgers

L'idée de code **asynchrone** décrite ci-dessus est parfois aussi appelée **"concurrence"**. Ce qui est différent du **"parallélisme"**.

La **concurrence** et le **parallélisme** sont tous deux liés à l'idée de "différentes choses arrivant plus ou moins au même moment".

Mais les détails entre la **concurrence** et le **parallélisme** diffèrent sur de nombreux points.

En ajoutant `standard`, Uvicorn va installer et utiliser quelques dépendances supplémentaires recommandées.

Cela inclut `uvloop`, le remplaçant performant de `asyncio`, qui fournit le gros gain de performance en matière de concurrence.

///

////

//// tab | Hypercorn

* <a href="https://github.com/pgjones/hypercorn" class="external-link" target="_blank">Hypercorn</a>, un serveur ASGI également compatible avec HTTP/2.

{* ../../docs_src/first_steps/tutorial003.py hl[7] *}

/// note

Si vous ne connaissez pas la différence, allez voir la section [Concurrence : *"Vous êtes pressés ?"*](../async.md#vous-etes-presses){.internal-link target=_blank}.

///

### Étape 5 : retourner le contenu

{* ../../docs_src/first_steps/tutorial001.py hl[8] *}

from typing import TypeVar

import anyio.to_thread
from anyio import CapacityLimiter
from starlette.concurrency import iterate_in_threadpool as iterate_in_threadpool  # noqa
from starlette.concurrency import run_in_threadpool as run_in_threadpool  # noqa
from starlette.concurrency import (  # noqa
    run_until_first_complete as run_until_first_complete,
)

_T = TypeVar("_T")


@asynccontextmanager

El cajero dice algo al cocinero en la cocina para que sepan que tienen que preparar tus hamburguesas (aunque actualmente están preparando las de los clientes anteriores).

<img src="/img/async/concurrent-burgers/concurrent-burgers-03.png" class="illustration">

Pagas. 💸

El cajero te da el número de tu turno.

### Concurrency and Burgers { #concurrency-and-burgers }

This idea of **asynchronous** code described above is also sometimes called **"concurrency"**. It is different from **"parallelism"**.

**Concurrency** and **parallelism** both relate to "different things happening more or less at the same time".

But the details between *concurrency* and *parallelism* are quite different.

import java.time.Duration;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.CancellationException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link FakeTicker}.
 *
 * @author Jige Yu
 */
@GwtCompatible

import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link FakeTicker}.
 *
 * @author Jige Yu
 */
@GwtCompatible

     * Stored as a long value representing milliseconds since epoch.
     * Used for audit trail and concurrency control.
     */
    @ValidateTypeFailure
    public Long updatedTime;

    /**
     * The version number of the elevate word configuration for optimistic locking.
     * This field is required to prevent concurrent modification conflicts
     * by ensuring the configuration hasn't been modified by another process.
     */