COPY ./app /code/app

# (1)!
CMD ["fastapi", "run", "app/main.py", "--port", "80", "--workers", "4"]
```

1. Hier verwenden wir die `--workers` Befehlszeilenoption, um die Anzahl der Worker auf 4 festzulegen.

Hier sind einige Beispiele, wann das sinnvoll sein könnte:

#### Eine einfache Anwendung { #a-simple-app }

	if (checkOld > 0 && len(p.workers) != checkOld) || n == len(p.workers) || n < 1 {
		// Either already satisfied or worker count changed while we waited for the lock.
		return
	}
	for len(p.workers) < n {
		input := make(chan ReplicationWorkerOperation, 10000)
		p.workers = append(p.workers, input)

		go p.AddWorker(input, &p.activeWorkers)
	}
	for len(p.workers) > n {
		worker := p.workers[len(p.workers)-1]

          "declarative-dsl-internal-utils",
          "javadoc",
          "kotlin-dsl-provider-plugins",
          "precondition-tester",
          "test-suites-base",
          "worker-main",
          "workers"
        ],
        "parallelizationMethod": {
          "numberOfBatches": 1,
          "name": "TeamCityParallelTests"
        }
      },
      {
        "subprojects": [

		workers = workers[:len(workers)-1]
		worker <- expiryOp(nil)
		es.stats.workers.Add(-1)
	}
	// Atomically replace workers.
	es.workers.Store(&workers)
}

// Worker handles 4 types of expiration tasks.
// 1. Expiry of objects, includes regular and transitioned objects
// 2. Expiry of noncurrent versions due to NewerNoncurrentVersions

Aquí hay algunas combinaciones y estrategias posibles:

* **Uvicorn** con `--workers`
    * Un administrador de procesos de Uvicorn **escucharía** en la **IP** y **puerto**, y iniciaría **múltiples worker processes de Uvicorn**.
* **Kubernetes** y otros sistemas de **contenedor distribuidos**

Here are some possible combinations and strategies:

* **Uvicorn** with `--workers`
    * One Uvicorn **process manager** would listen on the **IP** and **port**, and it would start **multiple Uvicorn worker processes**.
* **Kubernetes** and other distributed **container systems**

And if you need to have multiple workers, you can simply use the `--workers` command line option.

/// note | Technical Details

The Docker image was created when Uvicorn didn't support managing and restarting dead workers, so it was needed to use Gunicorn with Uvicorn, which added quite some complexity, just to have Gunicorn manage and restart the Uvicorn worker processes.

  /**
   * This counter prevents an ABA issue where a thread may successfully schedule the worker, the
   * worker runs and exhausts the queue, another thread enqueues a task and fails to schedule the
   * worker, and then the first thread's call to delegate.execute() returns. Without this counter,
   * it would observe the QUEUING state and set it to QUEUED, and the worker would never be
   * scheduled again for future submissions.
   */
  @GuardedBy("queue")

  /**
   * This counter prevents an ABA issue where a thread may successfully schedule the worker, the
   * worker runs and exhausts the queue, another thread enqueues a task and fails to schedule the
   * worker, and then the first thread's call to delegate.execute() returns. Without this counter,
   * it would observe the QUEUING state and set it to QUEUED, and the worker would never be
   * scheduled again for future submissions.
   */
  @GuardedBy("queue")

Y si necesitas tener múltiples workers, puedes simplemente utilizar la opción de línea de comandos `--workers`.

/// note | Detalles Técnicos

La imagen de Docker se creó cuando Uvicorn no soportaba gestionar y reiniciar workers muertos, por lo que era necesario usar Gunicorn con Uvicorn, lo que añadía bastante complejidad, solo para que Gunicorn gestionara y reiniciara los worker processes de Uvicorn.