终止 Actor#

在 Python 中,当所有 Actor 句柄副本超出作用域时,或当原始创建者进程死亡时,Actor 进程将自动终止。

请注意,Java 或 C++ 尚不支持 Actor 的自动终止。

通过 Actor 句柄手动终止#

在大多数情况下,Ray 会自动终止超出作用域的 Actor,但有时您可能需要强制终止 Actor。这仅适用于 Actor 意外挂起或资源泄漏的情况,以及必须手动销毁的分离 Actor

import ray

@ray.remote
class Actor:
    pass

actor_handle = Actor.remote()

ray.kill(actor_handle)
# This will not go through the normal Python sys.exit
# teardown logic, so any exit handlers installed in
# the actor using ``atexit`` will not be called.
actorHandle.kill();
// This will not go through the normal Java System.exit teardown logic, so any
// shutdown hooks installed in the actor using ``Runtime.addShutdownHook(...)`` will
// not be called.
actor_handle.Kill();
// This will not go through the normal C++ std::exit
// teardown logic, so any exit handlers installed in
// the actor using ``std::atexit`` will not be called.

这将导致 Actor 立即退出其进程,使得任何当前、待处理和未来的任务都因 RayActorError 而失败。如果您希望 Ray 自动重启 Actor,请确保在 Actor 的 @ray.remote 选项中设置一个非零的 max_restarts,然后将标志 no_restart=False 传递给 ray.kill

对于命名和分离 Actor,在 Actor 句柄上调用 ray.kill 会销毁 Actor 并允许名称被重复使用。

使用 State API 中的 ray list actors --detail 查看死亡 Actor 的死因

# This API is only available when you download Ray via `pip install "ray[default]"`
ray list actors --detail
---
-   actor_id: e8702085880657b355bf7ef001000000
    class_name: Actor
    state: DEAD
    job_id: '01000000'
    name: ''
    node_id: null
    pid: 0
    ray_namespace: dbab546b-7ce5-4cbb-96f1-d0f64588ae60
    serialized_runtime_env: '{}'
    required_resources: {}
    death_cause:
        actor_died_error_context: # <---- You could see the error message w.r.t why the actor exits.
            error_message: The actor is dead because `ray.kill` killed it.
            owner_id: 01000000ffffffffffffffffffffffffffffffffffffffffffffffff
            owner_ip_address: 127.0.0.1
            ray_namespace: dbab546b-7ce5-4cbb-96f1-d0f64588ae60
            class_name: Actor
            actor_id: e8702085880657b355bf7ef001000000
            never_started: true
            node_ip_address: ''
            pid: 0
            name: ''
    is_detached: false
    placement_group_id: null
    repr_name: ''

在 Actor 内部手动终止#

如有必要,您可以从 Actor 的方法内部手动终止 Actor。这将杀死 Actor 进程并释放与 Actor 关联/分配的资源。

@ray.remote
class Actor:
    def exit(self):
        ray.actor.exit_actor()

actor = Actor.remote()
actor.exit.remote()

通常不需要这种方法,因为 Actor 会自动进行垃圾回收。任务产生的 ObjectRef 可以被等待,以等待 Actor 退出(在其上调用 ray.get() 将引发 RayActorError)。

Ray.exitActor();

Actor 的垃圾回收尚未实现,因此这是目前唯一优雅地终止 Actor 的方法。任务产生的 ObjectRef 可以被等待,以等待 Actor 退出(在其上调用 ObjectRef::get 将抛出 RayActorException)。

ray::ExitActor();

Actor 的垃圾回收尚未实现,因此这是目前唯一优雅地终止 Actor 的方法。任务产生的 ObjectRef 可以被等待,以等待 Actor 退出(在其上调用 ObjectRef::Get 将抛出 RayActorException)。

请注意,这种终止方法会等待所有先前提交的任务执行完毕,然后使用 sys.exit 优雅地退出进程。

您可以看到 Actor 由于用户调用 exit_actor() 而死亡

# This API is only available when you download Ray via `pip install "ray[default]"`
ray list actors --detail
---
-   actor_id: 070eb5f0c9194b851bb1cf1602000000
    class_name: Actor
    state: DEAD
    job_id: '02000000'
    name: ''
    node_id: 47ccba54e3ea71bac244c015d680e202f187fbbd2f60066174a11ced
    pid: 47978
    ray_namespace: 18898403-dda0-485a-9c11-e9f94dffcbed
    serialized_runtime_env: '{}'
    required_resources: {}
    death_cause:
        actor_died_error_context:
            error_message: 'The actor is dead because its worker process has died.
                Worker exit type: INTENDED_USER_EXIT Worker exit detail: Worker exits
                by an user request. exit_actor() is called.'
            owner_id: 02000000ffffffffffffffffffffffffffffffffffffffffffffffff
            owner_ip_address: 127.0.0.1
            node_ip_address: 127.0.0.1
            pid: 47978
            ray_namespace: 18898403-dda0-485a-9c11-e9f94dffcbed
            class_name: Actor
            actor_id: 070eb5f0c9194b851bb1cf1602000000
            name: ''
            never_started: false
    is_detached: false
    placement_group_id: null
    repr_name: ''