Github user nkalmar commented on the pull request:
https://github.com/apache/zookeeper/commit/a2623a625a4778720f7d5482d0a66e9b37ae556f#commitcomment-29880817
@maoling It has been intentionally removed from 3.6 and 3.5, as I was told
the 4 letter words is deprecated, and it will be removed. No new metrics should
be introduced.---
