Hi all, I'd like to start a discussion on KIP-1387, which adds a stat that counts latency and size values into fixed bins and gives the bin counts to the metrics reporter.
KIP link: https://cwiki.apache.org/confluence/x/XwKDGw Client latency and size metrics today are an average and a maximum over a 30-second window. We don’t get a view into how the values are spread, a p99 can't be derived from them. A percentile computed inside the client can't be combined across clients or across windows whereas bin counts can. A reporter can publish them as a Prom or OTel histogram, and a backend query can compute any percentile, over any period across the whole fleet. The KIP adds DistributionStat, whose value is a DistributionSnapshot of cumulative bin counts. Seven distributions are registered at INFO next to the existing -avg and -max metrics, with more at DEBUG. Existing metrics don't change, and JmxReporter skips distributions, so a client reporting over JMX sees nothing new. Looking forward to your feedback. Thanks, Aditya
