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ray-project--ray/python/ray/air/tests/execution/test_e2e_train_flow.py
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2026-07-13 13:17:40 +08:00

267 lines
8.0 KiB
Python

import random
from typing import Any, List, Optional
import pytest
import ray
from ray.air import ResourceRequest
from ray.air.execution import FixedResourceManager, PlacementGroupResourceManager
from ray.air.execution._internal import Barrier
from ray.air.execution._internal.actor_manager import RayActorManager
from ray.air.execution._internal.tracked_actor import TrackedActor
from ray.exceptions import RayActorError
@pytest.fixture(scope="module")
def ray_start_4_cpus():
address_info = ray.init(num_cpus=4)
yield address_info
ray.shutdown()
@ray.remote
class Actor:
"""Simple actor for testing an execution flow.
This actor can fail in these ways:
1. On init if ``actor_init_kill`` is passed as a kwarg
2. On setup_1() if ``actor_setup_kill`` is passed as a kwarg (RayActorError)
3. On setup_1() if ``actor_setup_fail`` is passed as a kwarg (RayTaskError)
4. On train() if ``actor_train_kill`` is passed as a kwarg (RayTaskError)
5. On train() if ``actor_train_fail`` is passed as a kwarg (RayTaskError)
"""
def __init__(self, **kwargs):
self.kwargs = kwargs
if self.kwargs.get("actor_init_kill"):
raise RuntimeError("INIT")
def get_kwargs(self):
return self.kwargs
def setup_1(self):
if self.kwargs.get("actor_setup_kill"):
raise SystemExit
if self.kwargs.get("actor_setup_fail"):
raise RuntimeError("Setup")
return True
def setup_2(self):
return True
def train(self, value: float) -> float:
if value == 4:
if self.kwargs.get("actor_train_kill"):
# SystemExit will invoke a RayActorError
raise SystemExit
if self.kwargs.get("actor_train_fail"):
# RuntimeError will invoke a RayTaskError
raise RuntimeError("TASK")
return value
class TrainFlow:
"""This is a Ray Train-like execution flow.
- We want to run 4 actors in total ("trials")
- Each actor runs two init functions
- We train all actors in parallel for 10 iterations
- Errors can come up on actor construction, in the init functions,
or during training
- When an actor fails, restart that actor
- When a task fails, stop actor, and restart
"""
def __init__(
self, actor_manager: RayActorManager, errors: Optional[List[str]] = None
):
self._actor_manager = actor_manager
self._finished = False
self._actors_to_run = 4
self._tracked_actors = []
self._actors_stopped = 0
self._actors_to_replace = set()
self._ready_actors = set()
self._training_barrier = Barrier(
max_results=self._actors_to_run,
on_completion=self.training_barrier_completed,
)
self._restart_training = None
self._training_iter = 0
self._results = []
self._errors = errors
def setup_actors(self):
for actor_id in range(self._actors_to_run):
error_kwargs = {}
if self._errors:
error = random.choice(self._errors)
error_kwargs[error] = True
print("Actor", actor_id, "will be failing with", error_kwargs)
tracked_actor = self._actor_manager.add_actor(
cls=Actor,
kwargs={"id": actor_id, **error_kwargs},
resource_request=ResourceRequest([{"CPU": 1}]),
on_start=self.actor_started,
on_stop=self.actor_stopped,
on_error=self.actor_error,
)
self._tracked_actors.append(tracked_actor)
def actor_started(self, tracked_actor: TrackedActor):
self._actor_manager.schedule_actor_task(
tracked_actor,
"setup_1",
on_error=self.setup_error,
on_result=self.setup_1_result,
)
def actor_stopped(self, tracked_actor: TrackedActor):
self._ready_actors.discard(tracked_actor)
if tracked_actor in self._actors_to_replace:
self._replace_actor(tracked_actor=tracked_actor)
else:
self._actors_stopped += 1
self._finished = self._actors_stopped >= self._actors_to_run
def actor_error(self, tracked_actor: TrackedActor, exception: Exception):
self._ready_actors.discard(tracked_actor)
self._replace_actor(tracked_actor=tracked_actor)
def _replace_actor(self, tracked_actor: TrackedActor):
actor_index = self._tracked_actors.index(tracked_actor)
replacement_actor = self._actor_manager.add_actor(
cls=Actor,
kwargs={"id": actor_index},
resource_request=ResourceRequest([{"CPU": 1}]),
on_start=self.actor_started,
on_stop=self.actor_stopped,
on_error=self.actor_error,
)
self._tracked_actors[actor_index] = replacement_actor
def setup_1_result(self, tracked_actor: TrackedActor, result: Any):
self._actor_manager.schedule_actor_task(
tracked_actor,
"setup_2",
on_error=self.setup_error,
on_result=self.setup_2_result,
)
def setup_2_result(self, tracked_actor: TrackedActor, result: Any):
self._ready_actors.add(tracked_actor)
if len(self._ready_actors) == self._actors_to_run:
self.continue_training()
def setup_error(self, tracked_actor: TrackedActor, exception: Exception):
if isinstance(exception, RayActorError):
return
self._actors_to_replace.add(tracked_actor)
self._actor_manager.remove_actor(tracked_actor)
def continue_training(self):
if self._restart_training:
self._training_iter = self._restart_training
else:
self._training_iter += 1
self._training_barrier.reset()
self._actor_manager.schedule_actor_tasks(
self._tracked_actors,
"train",
args=(self._training_iter,),
on_result=self._training_barrier.arrive,
on_error=self.training_error,
)
def training_barrier_completed(self, barrier: Barrier):
self._results.append([res for _, res in barrier.get_results()])
self._restart_training = None
# If less than 10 epochs, continue training
if self._training_iter < 10:
return self.continue_training()
# Else, training finished
for tracked_actor in self._tracked_actors:
self._actor_manager.remove_actor(tracked_actor)
def training_error(self, tracked_actor: TrackedActor, exception: Exception):
self._restart_training = self._training_iter
if isinstance(exception, RayActorError):
return
self._actors_to_replace.add(tracked_actor)
self._ready_actors.discard(tracked_actor)
self._actor_manager.remove_actor(tracked_actor)
def run(self):
self.setup_actors()
while not self._finished:
self._actor_manager.next()
def get_results(self) -> List[List[float]]:
return self._results
@pytest.mark.parametrize(
"resource_manager_cls", [FixedResourceManager, PlacementGroupResourceManager]
)
@pytest.mark.parametrize(
"errors",
[
None,
"actor_init_kill",
"actor_setup_kill",
"actor_setup_fail",
"actor_train_kill",
"actor_train_fail",
# Chaos - every actor fails somehow, but in different ways
[
"actor_init_kill",
"actor_setup_kill",
"actor_setup_fail",
"actor_train_kill",
"actor_train_fail",
],
],
)
def test_e2e(ray_start_4_cpus, resource_manager_cls, errors):
actor_manager = RayActorManager(resource_manager=resource_manager_cls())
if errors and isinstance(errors, str):
errors = [errors]
flow = TrainFlow(actor_manager=actor_manager, errors=errors)
flow.run()
results = flow.get_results()
assert results == [[i] * 4 for i in range(1, 11)], results
if __name__ == "__main__":
import sys
sys.exit(pytest.main(["-v", __file__]))