Issue with passing pickled parameters when using Local Mode

System information

• OS Platform and Distribution Linux Ubuntu 16.04:
• **Ray installed from (source) **:
• Ray version 0.7.3:
• Python version 3.6.6:
• Exact command to reproduce:

Describe the problem

Hi Ray Team!

I use local mode when running some integration tests on a module that I have written using Ray, and I have noticed the functionality of ray change between update 0.7.2 and 0.7.3.

In 0.7.3 When I pass a pickled object as a parameter to my ray worker, I used to expect that the parameter would be returned to me as the pickled object, however while using local mode, it is returned to me as a LocalModeObjectID, and I am unable to retrieve the object using a call to ray.get

If I used 0.7.2 When I pass the same pickled object to my ray worker, it is returned to me as a the pickled object, of type bytes

Has there been an intended change in functionality in Ray’s local mode?

Source code / logs

[avnishn]

UPDATE: a small example to recreate the problem:

import ray
import pickle
@ray.remote
class ray_worker:

    def __init__(self, pckl_obj):
        self.pckl_obj = pickle.loads(pckl_obj)

if __name__ == "__main__":
    a = 5
    a = pickle.dumps(a)
    ray.init(local_mode=True)
    a_id = ray.put(a)
    worker = ray_worker.remote(a_id)

So the issue specifically happens if you put the pickled object in the object store using ray.put If I don’t ray.put the object into the object store, and instead directly pass the pickled object, then the example works fine.

[andrewv99]

I have only just started using ray / tune. I am experiencing the same issue / symptoms as @jasonnance. @edoakes , do you have any idea of when you might be able to look into this issue ? thanks