Hi Felix, Thanks for your feedback. Few questions below
On Wed, May 15, 2019 at 9:40 PM Felix Schumacher < [email protected]> wrote: > > Am 15.05.19 um 17:28 schrieb Philippe Mouawad: > > Hello, > > > > I'll start with my team the development of a switch to better percentiles > > computation which will end as a PR contribution. > > > > To recap previous discussions: > > > > - We have currently 2 implementations of Percentiles : > > - A custom one used in old listeners > > - A new one based on commons-math > > - CONS: > > - It impacts maintainability as a consequence > > - The results are different which confuses users > > - Percentiles are not explicitly documented regarding the algorithm > > used which also creates confusion : > > - https://github.com/apache/jmeter/pull/295 > > - https://github.com/apache/jmeter/pull/296 > > - Benefits: > > - Have one algorithm in codebase > > - Rely on best percentile algo for our use case > > - Rely on performing and reliable library HdrHistogram/LatencyUtils > > - Improve CO handling > > - PREVIOUS ACTIONS: > > - It was agreed that switching to HdrHistogram was a good option. This > > library is a standard now: > > - Used in MicroMeter (used by Spring) > > - Used in future JMC > > > https://mail.openjdk.java.net/pipermail/jmc-dev/2019-May/000984.html > > - Felix started a PR: > > - https://github.com/apache/jmeter/pull/380/files > > I updated the branch and thus the PR to be hopefully more correct than > the old one. > > I still have a few doubts about the implementation. It seems to me, that > HdrHistogram is good for collecting the stats, but not optimized for > asking the stats a lot while the test is running. > Which would affect GUI mode testing only right ? If confirmed we would need to reduce refresh rate ? > > That is the reason, that I tried to implement the calculation of some of > those stats myself. There is a good change, that I completely messed it up. > you mean " There is a good chance, that I completely messed it up." > > > - Vladimir mentioned LatencyUtils in this PR: > > - Used in MicroMeter > > - Based on Gil Tene work who is master of CO related issues as > > long as other titles > > > > > > *PROPOSED ACTION PLAN:* > > > > - We'll start our work using LatencyUtils which seems interesting as > it > > provides a PauseDetector which will be useful in our case > > > > > > If you have any note on this, feel free to add your ideas in this thread. > > Have a look at the performance of the reports while the stats are > collected. > Thanks > > Felix > > > > > Regards > > Philippe M. > > UbikLoadPack Team > > > > > > > > > > > > > > <https://www.openstreetmap.org/#map=18/50.69454/3.16455> > > > -- Cordialement. Philippe Mouawad.
