Zookeeper use cases with Kafka

[Prabhjot Bharaj <pr...@gmail.com>]

Hello Folks,

I wish to contribute to Kafka internals. And, one of the things which can
help me do that is understanding how kafka uses zookeeper. I have some of
these basic doubts:-

1. Is zookeeper primarily used for locking ? If yes, in what cases and what
kind of nodes does it use - sequential/ephemeral?

2. Does kafka use zookeeper watches for any of functions ?

3. What kind of state is stored in Zookeeper ? (I believe it has to be the
leader information per partition, but is there anything apart from it?)
What is the scale of data that is stored in Zookeeper ?

Looking forward for your help.

Thanks,
prabcs