Starting Java actors in different namespaces than the Ray driver

Ray Core
1

Can we start actors in a different namespace than the Ray driver in Ray’s Java API?

For context, in Python, we can set an actor’s namespace in the @remote decorator:

ray.init(namespace="driver-namespace")

@ray.remote(namespace="actor-namespace")
class ExampleActor:
    ...

# Starts ExampleActor in the
# "actor-namespace" namespace
ExampleActor.remote()

or the .options() call:

ray.init(namespace="driver-namespace")

# Starts ExampleActor in the
# "actor-namespace" namespace
ExampleActor.options(namespace="actor-namespace").remote()

From my understanding, in Java, the ActorCreatorOptions class lists all the potential actor options we can set. I don’t see a namespace option there:

  public final String name;
  public ActorLifetime lifetime;
  public final int maxRestarts;
  public final List<String> jvmOptions;
  public final int maxConcurrency;
  public final PlacementGroup group;
  public final int bundleIndex;
  public final List<ConcurrencyGroup> concurrencyGroups;
  public final String serializedRuntimeEnv;
  public final int maxPendingCalls;

Does this mean all Java Ray actors must start in the driver’s namespace?

How severe does this issue affect your experience of using Ray?
Medium: It contributes to significant difficulty to complete my task, but I can work around it.

2

@raulchen do we have this feature in ray java? Could you help someone on this question?

3

Just checked. This is not yet supported. Could you open an issue on GitHub? We will add this feature in the next version.
BTW, you can Ray.getActor with a different namespace.

4

Thanks @yic and @raulchen. I’ve opened an issue here: [Java] Allow Ray actors to start in a different namespace than the driver in Java API · Issue #25665 · ray-project/ray · GitHub