Files
2026-07-13 13:17:40 +08:00

83 lines
2.3 KiB
Python

import logging
from typing import Optional, TypeVar
from ray.train.v2._internal.execution.train_fn_utils import get_train_fn_utils
from ray.train.v2._internal.util import requires_train_worker
from ray.util.annotations import PublicAPI
T = TypeVar("T", bound=Optional[object])
logger = logging.getLogger(__file__)
@PublicAPI(stability="alpha")
@requires_train_worker()
def broadcast_from_rank_zero(data: T) -> T:
"""Broadcast small (<1kb) data from the rank 0 worker to all other workers.
Serves as a barrier, meaning that all workers must call this method before
the training function can continue.
Example:
.. testcode:
from ray.train import get_context
from ray.train.collective import broadcast_from_rank_zero
from ray.train.torch import TorchTrainer
def train_func():
...
if get_context().get_world_rank() == 0:
data = {"some_key": "some_value"}
else:
data = None
data = broadcast_from_rank_zero(data)
...
trainer = TorchTrainer(train_func)
trainer.fit()
Args:
data: The small (1kb) data to broadcast from the rank 0 worker to all
other workers.
Returns:
The data broadcasted from the rank 0 worker.
Raises:
ValueError: If the data is too big.
pickle.PicklingError: If the data is not pickleable.
TypeError: If the data is not pickleable.
"""
return get_train_fn_utils().broadcast_from_rank_zero(data)
@PublicAPI(stability="alpha")
@requires_train_worker()
def barrier() -> None:
"""Create a barrier across all workers.
All workers must call this method before the training function can continue.
Example:
.. testcode:
from ray.train import get_context
from ray.train.collective import barrier
from ray.train.torch import TorchTrainer
def train_func():
...
print(f"Rank {get_context().get_world_rank()} is waiting at the barrier.")
barrier()
print(f"Rank {get_context().get_world_rank()} has passed the barrier.")
...
trainer = TorchTrainer(train_func)
trainer.fit()
"""
return get_train_fn_utils().barrier()