ray.util.placement_group.PlacementGroup

class ray.util.placement_group.PlacementGroup(id: ray._raylet.PlacementGroupID, bundle_cache: Optional[List[Dict]] = None)

Bases: object

A handle to a placement group.

PublicAPI: This API is stable across Ray releases.

ready() → ray._raylet.ObjectRef

Returns an ObjectRef to check ready status.

This API runs a small dummy task to wait for placement group creation. It is compatible to ray.get and ray.wait.

Example

>>> import ray
>>> from ray.util.placement_group import PlacementGroup
>>> pg = PlacementGroup([{"CPU": 1}]) 
>>> ray.get(pg.ready()) 
>>> pg = PlacementGroup([{"CPU": 1}]) 
>>> ray.wait([pg.ready()], timeout=0) 

wait(timeout_seconds: Union[float, int] = 30) → bool

Wait for the placement group to be ready within the specified time. :param timeout_seconds: Timeout in seconds. :type timeout_seconds: float|int

Returns

True if the placement group is created. False otherwise.

property bundle_specs: List[Dict]

Return bundles belonging to this placement group.

Type

List[Dict]