Using Dask serialization in more cases

[jakirkham]

Looking through the code we can find a few examples of functions with arguments and keyword arguments serialized with cloudpickle. AFAICT this is used in the Client and the Workers. Though maybe it is used in other places as well. In these cases it would be nice to rely on the serialization mechanisms of the underlying Comm involved instead of simply pickling.

[mrocklin]

I don't have any objection here, other than code complexity. In practice functions like run are only really used for debugging, and so this hasn't come up with users. If there is an easy way to make this cleaner though then great.

[jakirkham]

Yeah I started playing with an idea in PR ( #3948 ). Need to test it a bit more still.

[dhirschfeld]

Is this related to:

• Serialize data within tasks #2110
• Custom Serialization for Task Args #2953

[jakirkham]

I don't think so. Though agree those would be nice to solve as well.