/**
   * 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")

        «««
        # FastAPI in Containers - Docker { #fastapi-in-containers-docker }
        »»»

    Translate with (German) – notice the dash:

        «««
        # FastAPI in Containern – Docker { #fastapi-in-containers-docker }
        »»»

    Do NOT translate with (German) – notice the hyphen:

        «««
        # FastAPI in Containern - Docker { #fastapi-in-containers-docker }
        »»»

```console
$ gunicorn main:app --workers 4 --worker-class uvicorn.workers.UvicornWorker --bind 0.0.0.0:80

[19499] [INFO] Starting gunicorn 20.1.0
[19499] [INFO] Listening at: http://0.0.0.0:80 (19499)
[19499] [INFO] Using worker: uvicorn.workers.UvicornWorker
[19511] [INFO] Booting worker with pid: 19511
[19513] [INFO] Booting worker with pid: 19513
[19514] [INFO] Booting worker with pid: 19514

```console
$ gunicorn main:app --workers 4 --worker-class uvicorn.workers.UvicornWorker --bind 0.0.0.0:80

[19499] [INFO] Starting gunicorn 20.1.0
[19499] [INFO] Listening at: http://0.0.0.0:80 (19499)
[19499] [INFO] Using worker: uvicorn.workers.UvicornWorker
[19511] [INFO] Booting worker with pid: 19511
[19513] [INFO] Booting worker with pid: 19513
[19514] [INFO] Booting worker with pid: 19514

* the task
* the background task
* the task function

* the template
* the template engine

* the type annotation
* the type hint

* the server worker
* the Uvicorn worker
* the Gunicorn Worker
* the worker process
* the worker class
* the workload

* the deployment
* to deploy

* the SDK
* the software development kit

* the `APIRouter`
* the `requirements.txt`

/// tip

Don't worry if some of these items about **containers**, Docker, or Kubernetes don't make a lot of sense yet.

I'll tell you more about container images, Docker, Kubernetes, etc. in a future chapter: [FastAPI in Containers - Docker](docker.md){.internal-link target=_blank}.

///

## Previous Steps Before Starting { #previous-steps-before-starting }

/// tip | Consejo

No te preocupes si algunos de estos elementos sobre **contenedores**, Docker, o Kubernetes no tienen mucho sentido todavía.

Te contaré más sobre imágenes de contenedores, Docker, Kubernetes, etc. en un capítulo futuro: [FastAPI en Contenedores - Docker](docker.md){.internal-link target=_blank}.

///

## Pasos Previos Antes de Iniciar { #previous-steps-before-starting }

#### Docker Compose { #docker-compose }

You could be deploying to a **single server** (not a cluster) with **Docker Compose**, so you wouldn't have an easy way to manage replication of containers (with Docker Compose) while preserving the shared network and **load balancing**.

Then you could want to have **a single container** with a **process manager** starting **several worker processes** inside.

---

下面一些什么时候这种做法有意义的示例：


#### 一个简单的应用程序

如果你的应用程序**足够简单**，你不需要（至少现在不需要）过多地微调进程数量，并且你可以使用自动默认值，那么你可能需要容器中的进程管理器 （使用官方 Docker 镜像），并且你在**单个服务器**而不是集群上运行它。

#### Docker Compose

你可以使用 **Docker Compose** 部署到**单个服务器**（而不是集群），因此你没有一种简单的方法来管理容器的复制（使用 Docker Compose），同时保留共享网络和 **负载均衡**。