Question about maxParallelIndexers

I have a couple of questions about maxParallelIndexers.

  1. How come /settings/maxParallelIndexers returns value for only one node while I have 3 nodes in the cluster.
  2. Each of the nodes has 4 CPUs and they often die when rebalancing (because of I have too many design_docs == 9). CPUs are overly used and the server easily goes down. So I am wondering if I lower maxParallelIndexers to 3 and indexAwareRebalanceDisabled to true, would it helps to perform rebalancing without any server down issue?

This topic is related to my old post.

Thank you very much for your time to respond.