Thanks Arshad for the good analysis. >>>> How can we go about getting these fixes?
Please feel free to raise an improvement task under ZK project issue tracker, URL: https://issues.apache.org/jira/browse/ZOOKEEPER Also, I'd appreciate if you can put a patch to fix it. Probably you can refer how to contribute to the project section, https://cwiki.apache.org/confluence/display/ZOOKEEPER/HowToContribute On Fri, Dec 2, 2016 at 3:25 AM, allen chan <[email protected]> wrote: > Arshad, > How can we go about getting these fixes? > > > On Thu, Dec 1, 2016 at 12:01 PM, Arshad Mohammad < > [email protected]> wrote: > > > 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 > > > > > > > > > -- > Allen Michael Chan >
