io.druid.indexing.overlord.RemoteTaskRunner - Exception while trying to assign task

So im testing druid data ingestion.
Basically it works for abouit 50-60 data batches I feed it and then it seemengly fails.

By fails I mean - cannot open indexer web console anymore and I see errors in the logs.

Overlord logs:

Coordinator log:

Any ideas?

You are running out of heap space for your overlord. How have you configured things?

I had to cancel this project and went with elk instead due to lack of time.