Changes where actor resources are assigned (#4323)

python/ray/actor.py

@@ -21,8 +21,6 @@ from ray.utils import _random_string
 from ray import (ObjectID, ActorID, ActorHandleID, ActorClassID, TaskID,
                  DriverID)
 
-DEFAULT_ACTOR_METHOD_NUM_RETURN_VALS = 1
-
 logger = logging.getLogger(__name__)
 
 
@@ -166,7 +164,7 @@ class ActorClass(object):
     """
 
     def __init__(self, modified_class, class_id, max_reconstructions, num_cpus,
-                 num_gpus, resources, actor_method_cpus):
+                 num_gpus, resources):
         self._modified_class = modified_class
         self._class_id = class_id
         self._class_name = modified_class.__name__
@@ -174,7 +172,6 @@ class ActorClass(object):
         self._num_cpus = num_cpus
         self._num_gpus = num_gpus
         self._resources = resources
-        self._actor_method_cpus = actor_method_cpus
         self._exported = False
 
         self._actor_methods = inspect.getmembers(
@@ -215,7 +212,7 @@ class ActorClass(object):
                     method.__ray_num_return_vals__)
             else:
                 self._actor_method_num_return_vals[method_name] = (
-                    DEFAULT_ACTOR_METHOD_NUM_RETURN_VALS)
+                    ray_constants.DEFAULT_ACTOR_METHOD_NUM_RETURN_VALS)
 
     def __call__(self, *args, **kwargs):
         raise Exception("Actors methods cannot be instantiated directly. "
@@ -276,6 +273,25 @@ class ActorClass(object):
         # updated to reflect the new invocation.
         actor_cursor = None
 
+        # 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.
+        if (self._num_cpus is None and self._num_gpus is None
+                and self._resources is None and num_cpus is None
+                and num_gpus is None and resources is None):
+            # In the default case, actors acquire no resources for
+            # their lifetime, and actor methods will require 1 CPU.
+            cpus_to_use = 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.
+            cpus_to_use = (ray_constants.DEFAULT_ACTOR_CREATION_CPU_SPECIFIED
+                           if self._num_cpus is None else self._num_cpus)
+            actor_method_cpu = ray_constants.DEFAULT_ACTOR_METHOD_CPU_SPECIFIED
+
         # Do not export the actor class or the actor if run in LOCAL_MODE
         # Instead, instantiate the actor locally and add it to the worker's
         # dictionary
@@ -290,15 +306,15 @@ class ActorClass(object):
                 self._exported = True
 
             resources = ray.utils.resources_from_resource_arguments(
-                self._num_cpus, self._num_gpus, self._resources, num_cpus,
+                cpus_to_use, self._num_gpus, self._resources, num_cpus,
                 num_gpus, resources)
 
             # 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 self._actor_method_cpus in [0, 1]
-            if self._actor_method_cpus == 1:
+            assert actor_method_cpu in [0, 1]
+            if actor_method_cpu == 1:
                 actor_placement_resources = resources.copy()
                 actor_placement_resources["CPU"] += 1
 
@@ -322,8 +338,8 @@ class ActorClass(object):
         actor_handle = ActorHandle(
             actor_id, self._modified_class.__module__, self._class_name,
             actor_cursor, self._actor_method_names, self._method_signatures,
-            self._actor_method_num_return_vals, actor_cursor,
-            self._actor_method_cpus, worker.task_driver_id)
+            self._actor_method_num_return_vals, actor_cursor, actor_method_cpu,
+            worker.task_driver_id)
         # We increment the actor counter by 1 to account for the actor creation
         # task.
         actor_handle._ray_actor_counter += 1
@@ -664,8 +680,7 @@ class ActorHandle(object):
         return self._deserialization_helper(state, False)
 
 
-def make_actor(cls, num_cpus, num_gpus, resources, actor_method_cpus,
-               max_reconstructions):
+def make_actor(cls, num_cpus, num_gpus, resources, max_reconstructions):
     # Give an error if cls is an old-style class.
     if not issubclass(cls, object):
         raise TypeError(
@@ -720,7 +735,7 @@ def make_actor(cls, num_cpus, num_gpus, resources, actor_method_cpus,
     class_id = ActorClassID(_random_string())
 
     return ActorClass(Class, class_id, max_reconstructions, num_cpus, num_gpus,
-                      resources, actor_method_cpus)
+                      resources)
 
 
 ray.worker.global_worker.make_actor = make_actor