Source code for ray.actor

import inspect
import logging
import weakref
from typing import Any, Dict, List, Optional, Union

import ray._private.ray_constants as ray_constants
import ray._private.signature as signature
import ray._private.worker
import ray._raylet
from ray import ActorClassID, Language, cross_language
from ray._private import ray_option_utils
from ray._private.async_compat import is_async_func
from ray._private.auto_init_hook import wrap_auto_init
from ray._private.client_mode_hook import (
    client_mode_convert_actor,
    client_mode_hook,
    client_mode_should_convert,
)
from ray._private.inspect_util import (
    is_class_method,
    is_function_or_method,
    is_static_method,
)
from ray._private.ray_option_utils import _warn_if_using_deprecated_placement_group
from ray._private.utils import get_runtime_env_info, parse_runtime_env
from ray._raylet import (
    STREAMING_GENERATOR_RETURN,
    ObjectRefGenerator,
    PythonFunctionDescriptor,
    raise_sys_exit_with_custom_error_message,
)
from ray.exceptions import AsyncioActorExit
from ray.util.annotations import DeveloperAPI, PublicAPI
from ray.util.placement_group import _configure_placement_group_based_on_context
from ray.util.scheduling_strategies import (
    PlacementGroupSchedulingStrategy,
    SchedulingStrategyT,
)
from ray.util.tracing.tracing_helper import (
    _inject_tracing_into_class,
    _tracing_actor_creation,
    _tracing_actor_method_invocation,
)

logger = logging.getLogger(__name__)

# Hook to call with (actor, resources, strategy) on each local actor creation.
_actor_launch_hook = None


[docs]@PublicAPI @client_mode_hook def method(*args, **kwargs): """Annotate an actor method. .. code-block:: python @ray.remote class Foo: @ray.method(num_returns=2) def bar(self): return 1, 2 f = Foo.remote() _, _ = f.bar.remote() Args: num_returns: The number of object refs that should be returned by invocations of this actor method. """ valid_kwargs = [ "num_returns", "concurrency_group", "max_task_retries", "retry_exceptions", "_generator_backpressure_num_objects", "enable_task_events", ] error_string = ( "The @ray.method decorator must be applied using at least one of " f"the arguments in the list {valid_kwargs}, for example " "'@ray.method(num_returns=2)'." ) assert len(args) == 0 and len(kwargs) > 0, error_string for key in kwargs: key_error_string = ( f"Unexpected keyword argument to @ray.method: '{key}'. The " f"supported keyword arguments are {valid_kwargs}" ) assert key in valid_kwargs, key_error_string def annotate_method(method): if "num_returns" in kwargs: method.__ray_num_returns__ = kwargs["num_returns"] if "max_task_retries" in kwargs: method.__ray_max_task_retries__ = kwargs["max_task_retries"] if "retry_exceptions" in kwargs: method.__ray_retry_exceptions__ = kwargs["retry_exceptions"] if "concurrency_group" in kwargs: method.__ray_concurrency_group__ = kwargs["concurrency_group"] if "_generator_backpressure_num_objects" in kwargs: method.__ray_generator_backpressure_num_objects__ = kwargs[ "_generator_backpressure_num_objects" ] if "enable_task_events" in kwargs and kwargs["enable_task_events"] is not None: method.__ray_enable_task_events__ = kwargs["enable_task_events"] return method return annotate_method
# Create objects to wrap method invocations. This is done so that we can # invoke methods with actor.method.remote() instead of actor.method(). @PublicAPI class ActorMethod: """A class used to invoke an actor method. Note: This class only keeps a weak ref to the actor, unless it has been passed to a remote function. This avoids delays in GC of the actor. Attributes: _actor_ref: A weakref handle to the actor. _method_name: The name of the actor method. _num_returns: The default number of return values that the method invocation should return. If None is given, it uses DEFAULT_ACTOR_METHOD_NUM_RETURN_VALS for a normal actor task and "streaming" for a generator task (when `is_generator` is True). _max_task_retries: Number of retries on method failure. _retry_exceptions: Boolean of whether you want to retry all user-raised exceptions, or a list of allowlist exceptions to retry. _is_generator: True if a given method is a Python generator. _generator_backpressure_num_objects: Generator-only config. If a number of unconsumed objects reach this threshold, a actor task stop pausing. enable_task_events: True if task events is enabled, i.e., task events from the actor should be reported. Defaults to True. _decorator: An optional decorator that should be applied to the actor method invocation (as opposed to the actor method execution) before invoking the method. The decorator must return a function that takes in two arguments ("args" and "kwargs"). In most cases, it should call the function that was passed into the decorator and return the resulting ObjectRefs. For an example, see "test_decorated_method" in "python/ray/tests/test_actor.py". """ def __init__( self, actor, method_name, num_returns: Optional[Union[int, str]], max_task_retries: int, retry_exceptions: Union[bool, list, tuple], is_generator: bool, generator_backpressure_num_objects: int, enable_task_events: bool, decorator=None, hardref=False, ): self._actor_ref = weakref.ref(actor) self._method_name = method_name self._num_returns = num_returns # Default case. if self._num_returns is None: if is_generator: self._num_returns = "streaming" else: self._num_returns = ray_constants.DEFAULT_ACTOR_METHOD_NUM_RETURN_VALS self._max_task_retries = max_task_retries self._retry_exceptions = retry_exceptions self._is_generator = is_generator self._generator_backpressure_num_objects = generator_backpressure_num_objects self._enable_task_events = enable_task_events # This is a decorator that is used to wrap the function invocation (as # opposed to the function execution). The decorator must return a # function that takes in two arguments ("args" and "kwargs"). In most # cases, it should call the function that was passed into the decorator # and return the resulting ObjectRefs. self._decorator = decorator # Acquire a hard ref to the actor, this is useful mainly when passing # actor method handles to remote functions. if hardref: self._actor_hard_ref = actor else: self._actor_hard_ref = None def __call__(self, *args, **kwargs): raise TypeError( "Actor methods cannot be called directly. Instead " f"of running 'object.{self._method_name}()', try " f"'object.{self._method_name}.remote()'." ) @DeveloperAPI def bind(self, *args, **kwargs): return self._bind(args, kwargs) def remote(self, *args, **kwargs): return self._remote(args, kwargs) def options(self, **options): """Convenience method for executing an actor method call with options. Same arguments as func._remote(), but returns a wrapped function that a non-underscore .remote() can be called on. Examples: # The following two calls are equivalent. >>> actor.my_method._remote(args=[x, y], name="foo", num_returns=2) >>> actor.my_method.options(name="foo", num_returns=2).remote(x, y) """ func_cls = self class FuncWrapper: def remote(self, *args, **kwargs): return func_cls._remote(args=args, kwargs=kwargs, **options) @DeveloperAPI def bind(self, *args, **kwargs): return func_cls._bind(args=args, kwargs=kwargs, **options) return FuncWrapper() @wrap_auto_init @_tracing_actor_method_invocation def _bind( self, args=None, kwargs=None, name="", num_returns=None, concurrency_group=None, _generator_backpressure_num_objects=None, ): from ray.dag.class_node import ( PARENT_CLASS_NODE_KEY, PREV_CLASS_METHOD_CALL_KEY, ClassMethodNode, ) # TODO(sang): unify option passing options = { "name": name, "num_returns": num_returns, "concurrency_group": concurrency_group, "_generator_backpressure_num_objects": _generator_backpressure_num_objects, } actor = self._actor_ref() if actor is None: # Ref is GC'ed. It happens when the actor handle is GC'ed # when bind is called. raise RuntimeError("Lost reference to actor") other_args_to_resolve = { PARENT_CLASS_NODE_KEY: actor, PREV_CLASS_METHOD_CALL_KEY: None, } node = ClassMethodNode( self._method_name, args, kwargs, options, other_args_to_resolve=other_args_to_resolve, ) return node @wrap_auto_init @_tracing_actor_method_invocation def _remote( self, args=None, kwargs=None, name="", num_returns=None, max_task_retries=None, retry_exceptions=None, concurrency_group=None, _generator_backpressure_num_objects=None, enable_task_events=None, ): if num_returns is None: num_returns = self._num_returns if max_task_retries is None: max_task_retries = self._max_task_retries if max_task_retries is None: max_task_retries = 0 if retry_exceptions is None: retry_exceptions = self._retry_exceptions if enable_task_events is None: enable_task_events = self._enable_task_events if _generator_backpressure_num_objects is None: _generator_backpressure_num_objects = ( self._generator_backpressure_num_objects ) def invocation(args, kwargs): actor = self._actor_hard_ref or self._actor_ref() if actor is None: raise RuntimeError("Lost reference to actor") return actor._actor_method_call( self._method_name, args=args, kwargs=kwargs, name=name, num_returns=num_returns, max_task_retries=max_task_retries, retry_exceptions=retry_exceptions, concurrency_group_name=concurrency_group, generator_backpressure_num_objects=( _generator_backpressure_num_objects ), enable_task_events=enable_task_events, ) # Apply the decorator if there is one. if self._decorator is not None: invocation = self._decorator(invocation) return invocation(args, kwargs) def __getstate__(self): return { "actor": self._actor_ref(), "method_name": self._method_name, "num_returns": self._num_returns, "max_task_retries": self._max_task_retries, "retry_exceptions": self._retry_exceptions, "decorator": self._decorator, "is_generator": self._is_generator, "generator_backpressure_num_objects": self._generator_backpressure_num_objects, # noqa "enable_task_events": self._enable_task_events, } def __setstate__(self, state): self.__init__( state["actor"], state["method_name"], state["num_returns"], state["max_task_retries"], state["retry_exceptions"], state["is_generator"], state["generator_backpressure_num_objects"], state["enable_task_events"], state["decorator"], hardref=True, ) class _ActorClassMethodMetadata(object): """Metadata for all methods in an actor class. This data can be cached. Attributes: methods: The actor methods. decorators: Optional decorators that should be applied to the method invocation function before invoking the actor methods. These can be set by attaching the attribute "__ray_invocation_decorator__" to the actor method. signatures: The signatures of the methods. num_returns: The default number of return values for each actor method. max_task_retries: Number of retries on method failure. retry_exceptions: Boolean of whether you want to retry all user-raised exceptions, or a list of allowlist exceptions to retry, for each method. enable_task_events: True if tracing is enabled, i.e., task events from the actor should be reported. Defaults to True. """ _cache = {} # This cache will be cleared in ray._private.worker.disconnect() def __init__(self): class_name = type(self).__name__ raise TypeError( f"{class_name} can not be constructed directly, " f"instead of running '{class_name}()', " f"try '{class_name}.create()'" ) @classmethod def reset_cache(cls): cls._cache.clear() @classmethod def create(cls, modified_class, actor_creation_function_descriptor): # Try to create an instance from cache. cached_meta = cls._cache.get(actor_creation_function_descriptor) if cached_meta is not None: return cached_meta # Create an instance without __init__ called. self = cls.__new__(cls) actor_methods = inspect.getmembers(modified_class, is_function_or_method) self.methods = dict(actor_methods) # Extract the signatures of each of the methods. This will be used # to catch some errors if the methods are called with inappropriate # arguments. self.decorators = {} self.signatures = {} self.num_returns = {} self.max_task_retries = {} self.retry_exceptions = {} self.method_is_generator = {} self.enable_task_events = {} self.generator_backpressure_num_objects = {} self.concurrency_group_for_methods = {} for method_name, method in actor_methods: # Whether or not this method requires binding of its first # argument. For class and static methods, we do not want to bind # the first argument, but we do for instance methods method = inspect.unwrap(method) is_bound = is_class_method(method) or is_static_method( modified_class, method_name ) # Print a warning message if the method signature is not # supported. We don't raise an exception because if the actor # inherits from a class that has a method whose signature we # don't support, there may not be much the user can do about it. self.signatures[method_name] = signature.extract_signature( method, ignore_first=not is_bound ) # Set the default number of return values for this method. if hasattr(method, "__ray_num_returns__"): self.num_returns[method_name] = method.__ray_num_returns__ else: self.num_returns[method_name] = None # Only contains entries from `@ray.method(max_task_retries=...)` # Ray may not populate the others with max_task_retries here because you may # have set in `actor.method.options(max_task_retries=...)`. So Ray always # stores max_task_retries both from the method and from the actor, and # favors the former. if hasattr(method, "__ray_max_task_retries__"): self.max_task_retries[method_name] = method.__ray_max_task_retries__ if hasattr(method, "__ray_retry_exceptions__"): self.retry_exceptions[method_name] = method.__ray_retry_exceptions__ if hasattr(method, "__ray_invocation_decorator__"): self.decorators[method_name] = method.__ray_invocation_decorator__ if hasattr(method, "__ray_concurrency_group__"): self.concurrency_group_for_methods[ method_name ] = method.__ray_concurrency_group__ if hasattr(method, "__ray_enable_task_events__"): self.enable_task_events[method_name] = method.__ray_enable_task_events__ is_generator = inspect.isgeneratorfunction( method ) or inspect.isasyncgenfunction(method) self.method_is_generator[method_name] = is_generator if hasattr(method, "__ray_generator_backpressure_num_objects__"): self.generator_backpressure_num_objects[ method_name ] = method.__ray_generator_backpressure_num_objects__ # Update cache. cls._cache[actor_creation_function_descriptor] = self return self class _ActorClassMetadata: """Metadata for an actor class. Attributes: language: The actor language, e.g. Python, Java. modified_class: The original class that was decorated (with some additional methods added like __ray_terminate__). actor_creation_function_descriptor: The function descriptor for the actor creation task. class_id: The ID of this actor class. class_name: The name of this class. num_cpus: The default number of CPUs required by the actor creation task. num_gpus: The default number of GPUs required by the actor creation task. memory: The heap memory quota for this actor. resources: The default resources required by the actor creation task. accelerator_type: The specified type of accelerator required for the node on which this actor runs. See :ref:`accelerator types <accelerator_types>`. runtime_env: The runtime environment for this actor. scheduling_strategy: Strategy about how to schedule this actor. last_export_session_and_job: A pair of the last exported session and job to help us to know whether this function was exported. This is an imperfect mechanism used to determine if we need to export the remote function again. It is imperfect in the sense that the actor class definition could be exported multiple times by different workers. method_meta: The actor method metadata. """ def __init__( self, language, modified_class, actor_creation_function_descriptor, class_id, max_restarts, max_task_retries, num_cpus, num_gpus, memory, object_store_memory, resources, accelerator_type, runtime_env, concurrency_groups, scheduling_strategy: SchedulingStrategyT, ): self.language = language self.modified_class = modified_class self.actor_creation_function_descriptor = actor_creation_function_descriptor self.class_name = actor_creation_function_descriptor.class_name self.is_cross_language = language != Language.PYTHON self.class_id = class_id self.max_restarts = max_restarts self.max_task_retries = max_task_retries self.num_cpus = num_cpus self.num_gpus = num_gpus self.memory = memory self.object_store_memory = object_store_memory self.resources = resources self.accelerator_type = accelerator_type self.runtime_env = runtime_env self.concurrency_groups = concurrency_groups self.scheduling_strategy = scheduling_strategy self.last_export_session_and_job = None self.method_meta = _ActorClassMethodMetadata.create( modified_class, actor_creation_function_descriptor ) @PublicAPI class ActorClassInheritanceException(TypeError): pass def _process_option_dict(actor_options): _filled_options = {} arg_names = set(inspect.getfullargspec(_ActorClassMetadata.__init__)[0]) for k, v in ray_option_utils.actor_options.items(): if k in arg_names: _filled_options[k] = actor_options.get(k, v.default_value) _filled_options["runtime_env"] = parse_runtime_env(_filled_options["runtime_env"]) return _filled_options @PublicAPI class ActorClass: """An actor class. This is a decorated class. It can be used to create actors. Attributes: __ray_metadata__: Contains metadata for the actor. """ def __init__(cls, name, bases, attr): """Prevents users from directly inheriting from an ActorClass. This will be called when a class is defined with an ActorClass object as one of its base classes. To intentionally construct an ActorClass, use the '_ray_from_modified_class' classmethod. Raises: ActorClassInheritanceException: When ActorClass is inherited. AssertionError: If ActorClassInheritanceException is not raised i.e., conditions for raising it are not met in any iteration of the loop. TypeError: In all other cases. """ for base in bases: if isinstance(base, ActorClass): raise ActorClassInheritanceException( f"Attempted to define subclass '{name}' of actor " f"class '{base.__ray_metadata__.class_name}'. " "Inheriting from actor classes is " "not currently supported. You can instead " "inherit from a non-actor base class and make " "the derived class an actor class (with " "@ray.remote)." ) # This shouldn't be reached because one of the base classes must be # an actor class if this was meant to be subclassed. assert False, ( "ActorClass.__init__ should not be called. Please use " "the @ray.remote decorator instead." ) def __call__(self, *args, **kwargs): """Prevents users from directly instantiating an ActorClass. This will be called instead of __init__ when 'ActorClass()' is executed because an is an object rather than a metaobject. To properly instantiated a remote actor, use 'ActorClass.remote()'. Raises: Exception: Always. """ raise TypeError( "Actors cannot be instantiated directly. " f"Instead of '{self.__ray_metadata__.class_name}()', " f"use '{self.__ray_metadata__.class_name}.remote()'." ) @classmethod def _ray_from_modified_class( cls, modified_class, class_id, actor_options, ): for attribute in [ "remote", "_remote", "_ray_from_modified_class", "_ray_from_function_descriptor", ]: if hasattr(modified_class, attribute): logger.warning( "Creating an actor from class " f"{modified_class.__name__} overwrites " f"attribute {attribute} of that class" ) # Make sure the actor class we are constructing inherits from the # original class so it retains all class properties. class DerivedActorClass(cls, modified_class): def __init__(self, *args, **kwargs): try: cls.__init__(self, *args, **kwargs) except Exception as e: # Delegate call to modified_class.__init__ only # if the exception raised by cls.__init__ is # TypeError and not ActorClassInheritanceException(TypeError). # In all other cases proceed with raise e. if isinstance(e, TypeError) and not isinstance( e, ActorClassInheritanceException ): modified_class.__init__(self, *args, **kwargs) else: raise e name = f"ActorClass({modified_class.__name__})" DerivedActorClass.__module__ = modified_class.__module__ DerivedActorClass.__name__ = name DerivedActorClass.__qualname__ = name # Construct the base object. self = DerivedActorClass.__new__(DerivedActorClass) # Actor creation function descriptor. actor_creation_function_descriptor = PythonFunctionDescriptor.from_class( modified_class.__ray_actor_class__ ) self.__ray_metadata__ = _ActorClassMetadata( Language.PYTHON, modified_class, actor_creation_function_descriptor, class_id, **_process_option_dict(actor_options), ) self._default_options = actor_options if "runtime_env" in self._default_options: self._default_options["runtime_env"] = self.__ray_metadata__.runtime_env return self @classmethod def _ray_from_function_descriptor( cls, language, actor_creation_function_descriptor, actor_options, ): self = ActorClass.__new__(ActorClass) self.__ray_metadata__ = _ActorClassMetadata( language, None, actor_creation_function_descriptor, None, **_process_option_dict(actor_options), ) self._default_options = actor_options if "runtime_env" in self._default_options: self._default_options["runtime_env"] = self.__ray_metadata__.runtime_env return self def remote(self, *args, **kwargs): """Create an actor. Args: args: These arguments are forwarded directly to the actor constructor. kwargs: These arguments are forwarded directly to the actor constructor. Returns: A handle to the newly created actor. """ return self._remote(args=args, kwargs=kwargs, **self._default_options)
[docs] def options(self, **actor_options): """Configures and overrides the actor instantiation parameters. The arguments are the same as those that can be passed to :obj:`ray.remote`. Args: num_cpus: The quantity of CPU cores to reserve for this task or for the lifetime of the actor. num_gpus: The quantity of GPUs to reserve for this task or for the lifetime of the actor. resources (Dict[str, float]): The quantity of various custom resources to reserve for this task or for the lifetime of the actor. This is a dictionary mapping strings (resource names) to floats. accelerator_type: If specified, requires that the task or actor run on a node with the specified type of accelerator. See :ref:`accelerator types <accelerator_types>`. memory: The heap memory request in bytes for this task/actor, rounded down to the nearest integer. object_store_memory: The object store memory request for actors only. max_restarts: This specifies the maximum number of times that the actor should be restarted when it dies unexpectedly. The minimum valid value is 0 (default), which indicates that the actor doesn't need to be restarted. A value of -1 indicates that an actor should be restarted indefinitely. max_task_retries: How many times to retry an actor task if the task fails due to a runtime error, e.g., the actor has died. If set to -1, the system will retry the failed task until the task succeeds, or the actor has reached its max_restarts limit. If set to `n > 0`, the system will retry the failed task up to n times, after which the task will throw a `RayActorError` exception upon :obj:`ray.get`. Note that Python exceptions may trigger retries *only if* `retry_exceptions` is set for the method, in that case when `max_task_retries` runs out the task will rethrow the exception from the task. You can override this number with the method's `max_task_retries` option in `@ray.method` decorator or in `.option()`. max_pending_calls: Set the max number of pending calls allowed on the actor handle. When this value is exceeded, PendingCallsLimitExceeded will be raised for further tasks. Note that this limit is counted per handle. -1 means that the number of pending calls is unlimited. max_concurrency: The max number of concurrent calls to allow for this actor. This only works with direct actor calls. The max concurrency defaults to 1 for threaded execution, and 1000 for asyncio execution. Note that the execution order is not guaranteed when max_concurrency > 1. name: The globally unique name for the actor, which can be used to retrieve the actor via ray.get_actor(name) as long as the actor is still alive. namespace: Override the namespace to use for the actor. By default, actors are created in an anonymous namespace. The actor can be retrieved via ray.get_actor(name=name, namespace=namespace). lifetime: Either `None`, which defaults to the actor will fate share with its creator and will be deleted once its refcount drops to zero, or "detached", which means the actor will live as a global object independent of the creator. runtime_env (Dict[str, Any]): Specifies the runtime environment for this actor or task and its children. See :ref:`runtime-environments` for detailed documentation. scheduling_strategy: Strategy about how to schedule a remote function or actor. Possible values are None: ray will figure out the scheduling strategy to use, it will either be the PlacementGroupSchedulingStrategy using parent's placement group if parent has one and has placement_group_capture_child_tasks set to true, or "DEFAULT"; "DEFAULT": default hybrid scheduling; "SPREAD": best effort spread scheduling; `PlacementGroupSchedulingStrategy`: placement group based scheduling; `NodeAffinitySchedulingStrategy`: node id based affinity scheduling. _metadata: Extended options for Ray libraries. For example, _metadata={"workflows.io/options": <workflow options>} for Ray workflows. enable_task_events: True if tracing is enabled, i.e., task events from the actor should be reported. Defaults to True. Examples: .. code-block:: python @ray.remote(num_cpus=2, resources={"CustomResource": 1}) class Foo: def method(self): return 1 # Class Bar will require 1 cpu instead of 2. # It will also require no custom resources. Bar = Foo.options(num_cpus=1, resources=None) """ actor_cls = self # override original options default_options = self._default_options.copy() # "concurrency_groups" could not be used in ".options()", # we should remove it before merging options from '@ray.remote'. default_options.pop("concurrency_groups", None) updated_options = ray_option_utils.update_options( default_options, actor_options ) ray_option_utils.validate_actor_options(updated_options, in_options=True) # only update runtime_env when ".options()" specifies new runtime_env if "runtime_env" in actor_options: updated_options["runtime_env"] = parse_runtime_env( updated_options["runtime_env"] ) class ActorOptionWrapper: def remote(self, *args, **kwargs): return actor_cls._remote(args=args, kwargs=kwargs, **updated_options) @DeveloperAPI def bind(self, *args, **kwargs): """ For Ray DAG building that creates static graph from decorated class or functions. """ from ray.dag.class_node import ClassNode return ClassNode( actor_cls.__ray_metadata__.modified_class, args, kwargs, updated_options, ) return ActorOptionWrapper()
@wrap_auto_init @_tracing_actor_creation def _remote(self, args=None, kwargs=None, **actor_options): """Create an actor. This method allows more flexibility than the remote method because resource requirements can be specified and override the defaults in the decorator. Args: args: The arguments to forward to the actor constructor. kwargs: The keyword arguments to forward to the actor constructor. num_cpus: The number of CPUs required by the actor creation task. num_gpus: The number of GPUs required by the actor creation task. memory: Restrict the heap memory usage of this actor. resources: The custom resources required by the actor creation task. max_concurrency: The max number of concurrent calls to allow for this actor. This only works with direct actor calls. The max concurrency defaults to 1 for threaded execution, and 1000 for asyncio execution. Note that the execution order is not guaranteed when max_concurrency > 1. name: The globally unique name for the actor, which can be used to retrieve the actor via ray.get_actor(name) as long as the actor is still alive. namespace: Override the namespace to use for the actor. By default, actors are created in an anonymous namespace. The actor can be retrieved via ray.get_actor(name=name, namespace=namespace). lifetime: Either `None`, which defaults to the actor will fate share with its creator and will be deleted once its refcount drops to zero, or "detached", which means the actor will live as a global object independent of the creator. placement_group: (This has been deprecated, please use `PlacementGroupSchedulingStrategy` scheduling_strategy) the placement group this actor belongs to, or None if it doesn't belong to any group. Setting to "default" autodetects the placement group based on the current setting of placement_group_capture_child_tasks. placement_group_bundle_index: (This has been deprecated, please use `PlacementGroupSchedulingStrategy` scheduling_strategy) the index of the bundle if the actor belongs to a placement group, which may be -1 to specify any available bundle. placement_group_capture_child_tasks: (This has been deprecated, please use `PlacementGroupSchedulingStrategy` scheduling_strategy) Whether or not children tasks of this actor should implicitly use the same placement group as its parent. It is False by default. runtime_env (Dict[str, Any]): Specifies the runtime environment for this actor or task and its children (see :ref:`runtime-environments` for details). max_pending_calls: Set the max number of pending calls allowed on the actor handle. When this value is exceeded, PendingCallsLimitExceeded will be raised for further tasks. Note that this limit is counted per handle. -1 means that the number of pending calls is unlimited. scheduling_strategy: Strategy about how to schedule this actor. enable_task_events: True if tracing is enabled, i.e., task events from the actor should be reported. Defaults to True. Returns: A handle to the newly created actor. """ name = actor_options.get("name") namespace = actor_options.get("namespace") if name is not None: if not isinstance(name, str): raise TypeError(f"name must be None or a string, got: '{type(name)}'.") elif name == "": raise ValueError("Actor name cannot be an empty string.") if namespace is not None: ray._private.utils.validate_namespace(namespace) # Handle the get-or-create case. if actor_options.get("get_if_exists"): try: return ray.get_actor(name, namespace=namespace) except ValueError: # Attempt to create it (may race with other attempts). updated_options = actor_options.copy() updated_options["get_if_exists"] = False # prevent infinite loop try: return self._remote(args, kwargs, **updated_options) except ValueError: # We lost the creation race, ignore. pass return ray.get_actor(name, namespace=namespace) # We pop the "concurrency_groups" coming from "@ray.remote" here. We no longer # need it in "_remote()". actor_options.pop("concurrency_groups", None) if args is None: args = [] if kwargs is None: kwargs = {} meta = self.__ray_metadata__ actor_has_async_methods = ( len(inspect.getmembers(meta.modified_class, predicate=is_async_func)) > 0 ) is_asyncio = actor_has_async_methods if actor_options.get("max_concurrency") is None: actor_options["max_concurrency"] = 1000 if is_asyncio else 1 if client_mode_should_convert(): return client_mode_convert_actor(self, args, kwargs, **actor_options) # fill actor required options for k, v in ray_option_utils.actor_options.items(): actor_options[k] = actor_options.get(k, v.default_value) # "concurrency_groups" already takes effects and should not apply again. # Remove the default value here. actor_options.pop("concurrency_groups", None) # TODO(suquark): cleanup these fields max_concurrency = actor_options["max_concurrency"] lifetime = actor_options["lifetime"] runtime_env = actor_options["runtime_env"] placement_group = actor_options["placement_group"] placement_group_bundle_index = actor_options["placement_group_bundle_index"] placement_group_capture_child_tasks = actor_options[ "placement_group_capture_child_tasks" ] scheduling_strategy = actor_options["scheduling_strategy"] max_restarts = actor_options["max_restarts"] max_task_retries = actor_options["max_task_retries"] max_pending_calls = actor_options["max_pending_calls"] # Override enable_task_events to default for actor if not specified (i.e. None) enable_task_events = actor_options.get("enable_task_events") if scheduling_strategy is None or not isinstance( scheduling_strategy, PlacementGroupSchedulingStrategy ): _warn_if_using_deprecated_placement_group(actor_options, 3) worker = ray._private.worker.global_worker worker.check_connected() # Check whether the name is already taken. # TODO(edoakes): this check has a race condition because two drivers # could pass the check and then create the same named actor. We should # instead check this when we create the actor, but that's currently an # async call. if name is not None: try: ray.get_actor(name, namespace=namespace) except ValueError: # Name is not taken. pass else: raise ValueError( f"The name {name} (namespace={namespace}) is already " "taken. Please use " "a different name or get the existing actor using " f"ray.get_actor('{name}', namespace='{namespace}')" ) if lifetime is None: detached = None elif lifetime == "detached": detached = True elif lifetime == "non_detached": detached = False else: raise ValueError( "actor `lifetime` argument must be one of 'detached', " "'non_detached' and 'None'." ) # LOCAL_MODE cannot handle cross_language if worker.mode == ray.LOCAL_MODE: assert ( not meta.is_cross_language ), "Cross language ActorClass cannot be executed locally." # Export the actor. if not meta.is_cross_language and ( meta.last_export_session_and_job != worker.current_session_and_job ): # If this actor class was not exported in this session and job, # we need to export this function again, because current GCS # doesn't have it. # After serialize / deserialize modified class, the __module__ # of modified class will be ray.cloudpickle.cloudpickle. # So, here pass actor_creation_function_descriptor to make # sure export actor class correct. worker.function_actor_manager.export_actor_class( meta.modified_class, meta.actor_creation_function_descriptor, meta.method_meta.methods.keys(), ) meta.last_export_session_and_job = worker.current_session_and_job resources = ray._private.utils.resources_from_ray_options(actor_options) # Set the actor's default resources if not already set. First three # conditions are to check that no resources were specified in the # decorator. Last three conditions are to check that no resources were # specified when _remote() was called. # TODO(suquark): In the original code, memory is not considered as resources, # when deciding the default CPUs. It is strange, but we keep the original # semantics in case that it breaks user applications & tests. if not set(resources.keys()).difference({"memory", "object_store_memory"}): # In the default case, actors acquire no resources for # their lifetime, and actor methods will require 1 CPU. resources.setdefault("CPU", ray_constants.DEFAULT_ACTOR_CREATION_CPU_SIMPLE) actor_method_cpu = ray_constants.DEFAULT_ACTOR_METHOD_CPU_SIMPLE else: # If any resources are specified (here or in decorator), then # all resources are acquired for the actor's lifetime and no # resources are associated with methods. resources.setdefault( "CPU", ray_constants.DEFAULT_ACTOR_CREATION_CPU_SPECIFIED ) actor_method_cpu = ray_constants.DEFAULT_ACTOR_METHOD_CPU_SPECIFIED # If the actor methods require CPU resources, then set the required # placement resources. If actor_placement_resources is empty, then # the required placement resources will be the same as resources. actor_placement_resources = {} assert actor_method_cpu in [0, 1] if actor_method_cpu == 1: actor_placement_resources = resources.copy() actor_placement_resources["CPU"] += 1 if meta.is_cross_language: creation_args = cross_language._format_args(worker, args, kwargs) else: function_signature = meta.method_meta.signatures["__init__"] creation_args = signature.flatten_args(function_signature, args, kwargs) if scheduling_strategy is None or isinstance( scheduling_strategy, PlacementGroupSchedulingStrategy ): # TODO(jjyao) Clean this up once the # placement_group option is removed. # We should also consider pushing this logic down to c++ # so that it can be reused by all languages. if isinstance(scheduling_strategy, PlacementGroupSchedulingStrategy): placement_group = scheduling_strategy.placement_group placement_group_bundle_index = ( scheduling_strategy.placement_group_bundle_index ) placement_group_capture_child_tasks = ( scheduling_strategy.placement_group_capture_child_tasks ) if placement_group_capture_child_tasks is None: placement_group_capture_child_tasks = ( worker.should_capture_child_tasks_in_placement_group ) placement_group = _configure_placement_group_based_on_context( placement_group_capture_child_tasks, placement_group_bundle_index, resources, actor_placement_resources, meta.class_name, placement_group=placement_group, ) if not placement_group.is_empty: scheduling_strategy = PlacementGroupSchedulingStrategy( placement_group, placement_group_bundle_index, placement_group_capture_child_tasks, ) else: scheduling_strategy = "DEFAULT" serialized_runtime_env_info = None if runtime_env is not None: serialized_runtime_env_info = get_runtime_env_info( runtime_env, is_job_runtime_env=False, serialize=True, ) concurrency_groups_dict = {} if meta.concurrency_groups is None: meta.concurrency_groups = [] for cg_name in meta.concurrency_groups: concurrency_groups_dict[cg_name] = { "name": cg_name, "max_concurrency": meta.concurrency_groups[cg_name], "function_descriptors": [], } # Update methods for method_name in meta.method_meta.concurrency_group_for_methods: cg_name = meta.method_meta.concurrency_group_for_methods[method_name] assert cg_name in concurrency_groups_dict module_name = meta.actor_creation_function_descriptor.module_name class_name = meta.actor_creation_function_descriptor.class_name concurrency_groups_dict[cg_name]["function_descriptors"].append( PythonFunctionDescriptor(module_name, method_name, class_name) ) # Update the creation descriptor based on number of arguments if meta.is_cross_language: func_name = "<init>" if meta.language == Language.CPP: func_name = meta.actor_creation_function_descriptor.function_name meta.actor_creation_function_descriptor = ( cross_language._get_function_descriptor_for_actor_method( meta.language, meta.actor_creation_function_descriptor, func_name, str(len(args) + len(kwargs)), ) ) actor_id = worker.core_worker.create_actor( meta.language, meta.actor_creation_function_descriptor, creation_args, max_restarts, max_task_retries, resources, actor_placement_resources, max_concurrency, detached, name if name is not None else "", namespace if namespace is not None else "", is_asyncio, # Store actor_method_cpu in actor handle's extension data. extension_data=str(actor_method_cpu), serialized_runtime_env_info=serialized_runtime_env_info or "{}", concurrency_groups_dict=concurrency_groups_dict or dict(), max_pending_calls=max_pending_calls, scheduling_strategy=scheduling_strategy, enable_task_events=enable_task_events, ) if _actor_launch_hook: _actor_launch_hook( meta.actor_creation_function_descriptor, resources, scheduling_strategy ) actor_handle = ActorHandle( meta.language, actor_id, max_task_retries, enable_task_events, meta.method_meta.method_is_generator, meta.method_meta.decorators, meta.method_meta.signatures, meta.method_meta.num_returns, meta.method_meta.max_task_retries, meta.method_meta.retry_exceptions, meta.method_meta.generator_backpressure_num_objects, meta.method_meta.enable_task_events, actor_method_cpu, meta.actor_creation_function_descriptor, worker.current_session_and_job, original_handle=True, ) return actor_handle @DeveloperAPI def bind(self, *args, **kwargs): """ For Ray DAG building that creates static graph from decorated class or functions. """ from ray.dag.class_node import ClassNode return ClassNode( self.__ray_metadata__.modified_class, args, kwargs, self._default_options ) @PublicAPI class ActorHandle: """A handle to an actor. The fields in this class are prefixed with _ray_ to hide them from the user and to avoid collision with actor method names. An ActorHandle can be created in three ways. First, by calling .remote() on an ActorClass. Second, by passing an actor handle into a task (forking the ActorHandle). Third, by directly serializing the ActorHandle (e.g., with cloudpickle). Attributes: _ray_actor_language: The actor language. _ray_actor_id: Actor ID. _ray_enable_task_events: The default value of whether task events is enabled, i.e., task events from the actor should be reported. _ray_method_is_generator: Map of method name -> if it is a generator method. _ray_method_decorators: Optional decorators for the function invocation. This can be used to change the behavior on the invocation side, whereas a regular decorator can be used to change the behavior on the execution side. _ray_method_signatures: The signatures of the actor methods. _ray_method_max_task_retries: Max number of retries on method failure. _ray_method_num_returns: The default number of return values for each method. _ray_method_retry_exceptions: The default value of boolean of whether you want to retry all user-raised exceptions, or a list of allowlist exceptions to retry. _ray_method_generator_backpressure_num_objects: Generator-only config. The max number of objects to generate before it starts pausing a generator. _ray_method_enable_task_events: The value of whether task tracing is enabled for the actor methods. This overrides the actor's default value (`_ray_enable_task_events`). _ray_actor_method_cpus: The number of CPUs required by actor methods. _ray_original_handle: True if this is the original actor handle for a given actor. If this is true, then the actor will be destroyed when this handle goes out of scope. _ray_is_cross_language: Whether this actor is cross language. _ray_actor_creation_function_descriptor: The function descriptor of the actor creation task. """ def __init__( self, language, actor_id, max_task_retries: Optional[int], enable_task_events: bool, method_is_generator: Dict[str, bool], method_decorators, method_signatures, method_num_returns: Dict[str, int], method_max_task_retries: Dict[str, int], method_retry_exceptions: Dict[str, Union[bool, list, tuple]], method_generator_backpressure_num_objects: Dict[str, int], method_enable_task_events: Dict[str, bool], actor_method_cpus: int, actor_creation_function_descriptor, session_and_job, original_handle=False, ): self._ray_actor_language = language self._ray_actor_id = actor_id self._ray_max_task_retries = max_task_retries self._ray_original_handle = original_handle self._ray_enable_task_events = enable_task_events self._ray_method_is_generator = method_is_generator self._ray_method_decorators = method_decorators self._ray_method_signatures = method_signatures self._ray_method_num_returns = method_num_returns self._ray_method_max_task_retries = method_max_task_retries self._ray_method_retry_exceptions = method_retry_exceptions self._ray_method_generator_backpressure_num_objects = ( method_generator_backpressure_num_objects ) self._ray_method_enable_task_events = method_enable_task_events self._ray_actor_method_cpus = actor_method_cpus self._ray_session_and_job = session_and_job self._ray_is_cross_language = language != Language.PYTHON self._ray_actor_creation_function_descriptor = ( actor_creation_function_descriptor ) self._ray_function_descriptor = {} if not self._ray_is_cross_language: assert isinstance( actor_creation_function_descriptor, PythonFunctionDescriptor ) module_name = actor_creation_function_descriptor.module_name class_name = actor_creation_function_descriptor.class_name for method_name in self._ray_method_signatures.keys(): function_descriptor = PythonFunctionDescriptor( module_name, method_name, class_name ) self._ray_function_descriptor[method_name] = function_descriptor method = ActorMethod( self, method_name, self._ray_method_num_returns[method_name], self._ray_method_max_task_retries.get( method_name, self._ray_max_task_retries ) or 0, # never None self._ray_method_retry_exceptions.get(method_name), self._ray_method_is_generator[method_name], self._ray_method_generator_backpressure_num_objects.get( method_name ), # noqa self._ray_method_enable_task_events.get( method_name, self._ray_enable_task_events, # Use actor's default value ), decorator=self._ray_method_decorators.get(method_name), ) setattr(self, method_name, method) def __del__(self): try: # Mark that this actor handle has gone out of scope. Once all actor # handles are out of scope, the actor will exit. if ray._private.worker: worker = ray._private.worker.global_worker if worker.connected and hasattr(worker, "core_worker"): worker.core_worker.remove_actor_handle_reference(self._ray_actor_id) except AttributeError: # Suppress the attribtue error which is caused by # python destruction ordering issue. # It only happen when python exits. pass def _actor_method_call( self, method_name: str, args: List[Any] = None, kwargs: Dict[str, Any] = None, name: str = "", num_returns: Optional[int] = None, max_task_retries: int = None, retry_exceptions: Union[bool, list, tuple] = None, concurrency_group_name: Optional[str] = None, generator_backpressure_num_objects: Optional[int] = None, enable_task_events: Optional[bool] = None, ): """Method execution stub for an actor handle. This is the function that executes when `actor.method_name.remote(*args, **kwargs)` is called. Instead of executing locally, the method is packaged as a task and scheduled to the remote actor instance. Args: method_name: The name of the actor method to execute. args: A list of arguments for the actor method. kwargs: A dictionary of keyword arguments for the actor method. name: The name to give the actor method call task. num_returns: The number of return values for the method. max_task_retries: Number of retries when method fails. retry_exceptions: Boolean of whether you want to retry all user-raised exceptions, or a list of allowlist exceptions to retry. enable_task_events: True if tracing is enabled, i.e., task events from the actor should be reported. Returns: object_refs: A list of object refs returned by the remote actor method. """ worker = ray._private.worker.global_worker args = args or [] kwargs = kwargs or {} if self._ray_is_cross_language: list_args = cross_language._format_args(worker, args, kwargs) function_descriptor = cross_language._get_function_descriptor_for_actor_method( # noqa: E501 self._ray_actor_language, self._ray_actor_creation_function_descriptor, method_name, # The signature for xlang should be "{length_of_arguments}" to handle # overloaded methods. signature=str(len(args) + len(kwargs)), ) else: function_signature = self._ray_method_signatures[method_name] if not args and not kwargs and not function_signature: list_args = [] else: list_args = signature.flatten_args(function_signature, args, kwargs) function_descriptor = self._ray_function_descriptor[method_name] if worker.mode == ray.LOCAL_MODE: assert ( not self._ray_is_cross_language ), "Cross language remote actor method cannot be executed locally." if num_returns == "dynamic": num_returns = -1 elif num_returns == "streaming": # TODO(sang): This is a temporary private API. # Remove it when we migrate to the streaming generator. num_returns = ray._raylet.STREAMING_GENERATOR_RETURN retry_exception_allowlist = None if retry_exceptions is None: retry_exceptions = False elif isinstance(retry_exceptions, (list, tuple)): retry_exception_allowlist = tuple(retry_exceptions) retry_exceptions = True assert isinstance( retry_exceptions, bool ), "retry_exceptions can either be \ boolean or list/tuple of exception types." if generator_backpressure_num_objects is None: generator_backpressure_num_objects = -1 object_refs = worker.core_worker.submit_actor_task( self._ray_actor_language, self._ray_actor_id, function_descriptor, list_args, name, num_returns, max_task_retries, retry_exceptions, retry_exception_allowlist, self._ray_actor_method_cpus, concurrency_group_name if concurrency_group_name is not None else b"", generator_backpressure_num_objects, enable_task_events, ) if num_returns == STREAMING_GENERATOR_RETURN: # Streaming generator will return a single ref # that is for the generator task. assert len(object_refs) == 1 generator_ref = object_refs[0] return ObjectRefGenerator(generator_ref, worker) if len(object_refs) == 1: object_refs = object_refs[0] elif len(object_refs) == 0: object_refs = None return object_refs def __getattr__(self, item): if not self._ray_is_cross_language: raise AttributeError( f"'{type(self).__name__}' object has " f"no attribute '{item}'" ) if item in ["__ray_terminate__"]: class FakeActorMethod(object): def __call__(self, *args, **kwargs): raise TypeError( "Actor methods cannot be called directly. Instead " "of running 'object.{}()', try 'object.{}.remote()'.".format( item, item ) ) def remote(self, *args, **kwargs): logger.warning( f"Actor method {item} is not supported by cross language." ) return FakeActorMethod() return ActorMethod( self, # actor item, # method_name ray_constants.DEFAULT_ACTOR_METHOD_NUM_RETURN_VALS, 0, # max_task_retries False, # retry_exceptions False, # is_generator self._ray_method_generator_backpressure_num_objects.get(item, -1), self._ray_enable_task_events, # enable_task_events # Currently, cross-lang actor method not support decorator decorator=None, ) # Make tab completion work. def __dir__(self): return self._ray_method_signatures.keys() def __repr__(self): return ( "Actor(" f"{self._ray_actor_creation_function_descriptor.class_name}, " f"{self._actor_id.hex()})" ) def __hash__(self): return hash(self._actor_id) def __eq__(self, __value): return hash(self) == hash(__value) @property def _actor_id(self): return self._ray_actor_id def _serialization_helper(self): """This is defined in order to make pickling work. Returns: A dictionary of the information needed to reconstruct the object. """ worker = ray._private.worker.global_worker worker.check_connected() if hasattr(worker, "core_worker"): # Non-local mode state = worker.core_worker.serialize_actor_handle(self._ray_actor_id) else: # Local mode state = ( { "actor_language": self._ray_actor_language, "actor_id": self._ray_actor_id, "max_task_retries": self._ray_max_task_retries, "enable_task_events": self._enable_task_events, "method_is_generator": self._ray_method_is_generator, "method_decorators": self._ray_method_decorators, "method_signatures": self._ray_method_signatures, "method_num_returns": self._ray_method_num_returns, "method_max_task_retries": self._ray_method_max_task_retries, "method_retry_exceptions": self._ray_method_retry_exceptions, "method_generator_backpressure_num_objects": ( self._ray_method_generator_backpressure_num_objects ), "method_enable_task_events": self._ray_method_enable_task_events, "actor_method_cpus": self._ray_actor_method_cpus, "actor_creation_function_descriptor": self._ray_actor_creation_function_descriptor, # noqa: E501 }, None, ) return state @classmethod def _deserialization_helper(cls, state, outer_object_ref=None): """This is defined in order to make pickling work. Args: state: The serialized state of the actor handle. outer_object_ref: The ObjectRef that the serialized actor handle was contained in, if any. This is used for counting references to the actor handle. """ worker = ray._private.worker.global_worker worker.check_connected() if hasattr(worker, "core_worker"): # Non-local mode return worker.core_worker.deserialize_and_register_actor_handle( state, outer_object_ref ) else: # Local mode return cls( # TODO(swang): Accessing the worker's current task ID is not # thread-safe. state["actor_language"], state["actor_id"], state["max_task_retries"], state["enable_task_events"], state["method_is_generator"], state["method_decorators"], state["method_signatures"], state["method_num_returns"], state["method_max_task_retries"], state["method_retry_exceptions"], state["method_generator_backpressure_num_objects"], state["method_enable_task_events"], state["actor_method_cpus"], state["actor_creation_function_descriptor"], worker.current_session_and_job, ) def __reduce__(self): """This code path is used by pickling but not by Ray forking.""" (serialized, _) = self._serialization_helper() # There is no outer object ref when the actor handle is # deserialized out-of-band using pickle. return ActorHandle._deserialization_helper, (serialized, None) def _modify_class(cls): # cls has been modified. if hasattr(cls, "__ray_actor_class__"): return cls # Give an error if cls is an old-style class. if not issubclass(cls, object): raise TypeError( "The @ray.remote decorator cannot be applied to old-style " "classes. In Python 2, you must declare the class with " "'class ClassName(object):' instead of 'class ClassName:'." ) # Modify the class to have additional default methods. class Class(cls): __ray_actor_class__ = cls # The original actor class def __ray_ready__(self): return True def __ray_call__(self, fn, *args, **kwargs): return fn(self, *args, **kwargs) def __ray_terminate__(self): worker = ray._private.worker.global_worker if worker.mode != ray.LOCAL_MODE: ray.actor.exit_actor() Class.__module__ = cls.__module__ Class.__name__ = cls.__name__ if not is_function_or_method(getattr(Class, "__init__", None)): # Add __init__ if it does not exist. # Actor creation will be executed with __init__ together. # Assign an __init__ function will avoid many checks later on. def __init__(self): pass Class.__init__ = __init__ return Class def _make_actor(cls, actor_options): Class = _modify_class(cls) _inject_tracing_into_class(Class) if "max_restarts" in actor_options: if actor_options["max_restarts"] != -1: # -1 represents infinite restart # Make sure we don't pass too big of an int to C++, causing # an overflow. actor_options["max_restarts"] = min( actor_options["max_restarts"], ray_constants.MAX_INT64_VALUE ) return ActorClass._ray_from_modified_class( Class, ActorClassID.from_random(), actor_options, ) @PublicAPI def exit_actor(): """Intentionally exit the current actor. This API can be used only inside an actor. Use ray.kill API if you'd like to kill an actor using actor handle. When the API is called, the actor raises an exception and exits. Any queued methods will fail. Any ``atexit`` handlers installed in the actor will be run. Raises: TypeError: An exception is raised if this is a driver or this worker is not an actor. """ worker = ray._private.worker.global_worker if worker.mode == ray.WORKER_MODE and not worker.actor_id.is_nil(): # In asyncio actor mode, we can't raise SystemExit because it will just # quit the asycnio event loop thread, not the main thread. Instead, we # raise a custom error to the main thread to tell it to exit. if worker.core_worker.current_actor_is_asyncio(): raise AsyncioActorExit() # Set a flag to indicate this is an intentional actor exit. This # reduces log verbosity. raise_sys_exit_with_custom_error_message("exit_actor() is called.") else: raise TypeError( "exit_actor API is called on a non-actor worker, " f"{worker.mode}. Call this API inside an actor methods" "if you'd like to exit the actor gracefully." )