Are you using nn.DistributedDataParallel as shown in this tutorial 178?
If so, I assume you are using a DistributedSampler to only use a valid subset of your dataset in each process?
In that case we should be able to add weighted sampling into the sampler, but let me know, if my assumptions are correct before diving into it. 



 James_Condon:

and have you considered running for president 2020?


Hahaha, president of discuss-land?