diff --git a/doc/source/multiprocessing.rst b/doc/source/multiprocessing.rst index af0129dac..21b7335f0 100644 --- a/doc/source/multiprocessing.rst +++ b/doc/source/multiprocessing.rst @@ -40,6 +40,9 @@ instructions to run on a multi-node Ray cluster instead. The full ``multiprocessing.Pool`` API is currently supported. Please see the `multiprocessing documentation`_ for details. +.. warning:: + The ``context`` argument in the ``Pool`` constructor is ignored when using Ray. + .. _`multiprocessing documentation`: https://docs.python.org/3/library/multiprocessing.html#module-multiprocessing.pool Run on a Cluster diff --git a/python/ray/experimental/multiprocessing/pool.py b/python/ray/experimental/multiprocessing/pool.py index 7ef361ec4..d3e4dbbd6 100644 --- a/python/ray/experimental/multiprocessing/pool.py +++ b/python/ray/experimental/multiprocessing/pool.py @@ -1,3 +1,4 @@ +import logging from multiprocessing import TimeoutError import os import time @@ -9,6 +10,8 @@ import copy import ray +logger = logging.getLogger(__name__) + RAY_ADDRESS_ENV = "RAY_ADDRESS" @@ -319,6 +322,7 @@ class Pool: initializer=None, initargs=None, maxtasksperchild=None, + context=None, ray_address=None): self._closed = False self._initializer = initializer @@ -326,6 +330,11 @@ class Pool: self._maxtasksperchild = maxtasksperchild or -1 self._actor_deletion_ids = [] + if context: + logger.warning("The 'context' argument is not supported using " + "ray. Please refer to the documentation for how " + "to control ray initialization.") + processes = self._init_ray(processes, ray_address) self._start_actor_pool(processes) @@ -339,12 +348,12 @@ class Pool: # Cluster mode. if ray_address is not None: - print("Connecting to ray cluster at address='{}'".format( + logger.info("Connecting to ray cluster at address='{}'".format( ray_address)) ray.init(address=ray_address) # Local mode. else: - print("Starting local ray cluster") + logger.info("Starting local ray cluster") ray.init(num_cpus=processes) ray_cpus = int(ray.state.cluster_resources()["CPU"])