lenskit.parallel.ray
====================

.. py:module:: lenskit.parallel.ray

.. autoapi-nested-parse::

   Support for parallelism with Ray.



Attributes
----------

.. autoapisummary::

   lenskit.parallel.ray.BATCH_SIZE


Classes
-------

.. toctree::
   :hidden:

   /api/lenskit/parallel/ray/TaskLimiter

.. autoapisummary::

   lenskit.parallel.ray.TaskLimiter


Functions
---------

.. autoapisummary::

   lenskit.parallel.ray.ensure_cluster
   lenskit.parallel.ray.init_cluster
   lenskit.parallel.ray.init_serializers
   lenskit.parallel.ray.ray_available
   lenskit.parallel.ray.ray_active
   lenskit.parallel.ray.is_ray_worker
   lenskit.parallel.ray.init_worker



Module Contents
---------------

.. py:data:: BATCH_SIZE
   :value: 200


.. py:function:: ensure_cluster()

.. py:function:: init_cluster(*, num_cpus = None, resources = None, global_logging = False, **kwargs)

   Initialize or connect to a Ray cluster, with the LensKit options.

   The resulting cluster can be used by an invoker, or it can be used directly.
   The Ray invoker uses batching, though, so it only works well with many small
   tasks.

   :param num_cpus: The total number of CPUs to allow. Defaults to
                    :fun:`effective_cpu_count`.
   :param proc_slots: The number of “process slots” for LensKit parallel operations.
                      Defaults to the LensKit process count.  These slots are recorded as
                      the ``lk_process`` resource on the Ray cluster.
   :param resources: Additional custom resources to register in the Ray cluster.
   :param global_logging: ``True`` to wire up logging in the workers at startup, instead of only
                          connecting logs when a task is run.
   :param kwargs: Other options to pass to :func:`ray.init`.

   :Stability: Experimental


.. py:function:: init_serializers()

.. py:function:: ray_available()

   Check if Ray is available.


.. py:function:: ray_active()

   Query whether Ray is active.


.. py:function:: is_ray_worker()

   Determine whether the current process is running on a Ray worker.


.. py:function:: init_worker(*, autostart = True)

   Initialize a Ray worker process.  Sets up logging, and returns the context.

   :param autostart: Set to ``False`` to disable calling :meth:`WorkerContext.start`, for
                     when the caller will start and stop the context if it is new.



Exported Aliases
----------------

.. py:function:: lenskit.parallel.ray.get_logger

    Re-exported alias for :py:func:`lenskit.logging.get_logger`.

.. py:class:: lenskit.parallel.ray.WorkerContext

    Re-exported alias for :py:class:`lenskit.logging.multiprocess.WorkerContext`.

.. py:class:: lenskit.parallel.ray.WorkerLogConfig

    Re-exported alias for :py:class:`lenskit.logging.multiprocess.WorkerLogConfig`.

.. py:function:: lenskit.parallel.ray.effective_cpu_count

    Re-exported alias for :py:func:`lenskit.parallel.config.effective_cpu_count`.

.. py:function:: lenskit.parallel.ray.ensure_parallel_init

    Re-exported alias for :py:func:`lenskit.parallel.config.ensure_parallel_init`.

.. py:function:: lenskit.parallel.ray.get_parallel_config

    Re-exported alias for :py:func:`lenskit.parallel.config.get_parallel_config`.