RayDaskCallback._ray_pretask(key, object_refs: List[ray._raylet.ObjectRef])[source]#

Run before executing a Dask task within a Ray task.

This method executes after Ray submits the task within a Ray worker. Ray passes the return value of this task to the _ray_posttask callback, if provided.

  • key – The Dask graph key for the Dask task.

  • object_refs – The object references for the arguments of the Ray task.


A value that Ray passes to the corresponding _ray_posttask callback, if the callback is defined.