Another simple question I was following this doc. https://docs.pinot.apache.org/operators/operating-pinot/tuning/realtime it mentioned 

*pinot.server.instance.realtime.alloc.offheap: true*.

But I am not able to get the format of Pinot server configuration, is it YAML or JSON? There is a parameter called  -configFileName. But it's description says 

Broker Starter Config file

. I am little confused here. Can anybody help?