Hi Alen AvgRequestLatency 0 implies that on an average time taken by the server to serve a request is less than one milli second. May be it is really 0 or it may be 0.99 ms.
This behaviour is not specific to 3.4.7 and 3.4.9 version but the same behaviour is there in all versions I find two reason whys AvgRequestLatency is almost all the time 0 1) Ping requests are counted the most: AvgRequestLatency is calculated as AvgRequestLatency=totalLatency/count Ping requests come very often and complete very fast, these request add nothing to totalLatency but add one to count. 2) Wrong data type is chosen to store AvgRequestLatency: AvgRequestLatency is calculated and store as the long value instead of double vlaue. In my opinion ZooKeeper code should be modified to improve this metrics i) Ping request should be ignored while recording the statistics or at least should be configurable whether to ignore or not. If ping request is not counted even other metrics will be more meaningful. ii) AvgRequestLatency should be of double type. -Arshad On Thu, Dec 1, 2016 at 4:50 AM, allen chan <[email protected]> wrote: > Anyone seeing this issue? I am experiencing it on 3.4.7 and 3.4.9 > > JMX metric name: AvgRequestLatency > JMX Location: > org.apache.ZooKeeperService:name0=ReplicatedServer_id#, > name1=replica.#,name2=[Leader|Follower]:AvgRequestLatency > > It always has a value of zero. The MaxRequestLatency is non-zero and > changes while the AvgRequestLatency always is zero. > > The zk_avg_latency metric in mntr is also zero. Is this metric not tracked > anymore? > > Thanks > -- > Allen Michael Chan >
