graphite data writer clarification

Gatling (Open-Source)
1

Hi,

I am using gatling version 3.3.1 and facing issue in graphite data writers

  1. I enabled graphite data writer and pushing logs to influx db. But I am seeing response time difference reported in graphite data and final gatling summary report.
  2. I am adding rootPathPrefix by following below, but prefix are not configured properly during runtime. Please advise
    object Engine extends App {

val GatConfig = scala.collection.mutable.Map(
data.graphite.RootPathPrefix → “qe.gatling.demo”
)
Gatling.fromMap(GatConfig)
}

Thanks and Regards,
Sakthivel Raja V

2

Assuming everything is properly configured, I would say not having the same response times in the HTML reports and InfluxDB is expected:

  • Gatling HTML reports split the run duration into up to 1,000 buckets by default and plot percentiles for each bucket
  • Gatling Graphite integration sends over the Graphite protocol percentiles every second (AFAIK, that’s the best that can be done with InfluxDB) and then InfluxDB will compute percentile averages (utterly wrong maths) to give you the desired number of plots.
    AFAIK, only FrontLine provides correct distributions at different resolutions.
3

Thanks stephane for your time.

Also, can you please advise below

  • Configured Gatling with maven
  • Using IntelliJ IDE
  • Separately added Engine.scala code as below to define rootPathPrefix configuration. But it is not working as expected.
    object Engine extends App {

val GatConfig = scala.collection.mutable.Map(
data.graphite.RootPathPrefix → “qe.gatling.demo”
)
Gatling.fromMap(GatConfig)
}

I am not seeing prefix in metrix/measurement. Should i mention anywhere to include this Engine.scala? it is under src/test/

Thanks and Regards,
Sakthivel Raja V

4

or is there any way to dynamically set rootPathPrefix through extending class in scala?

I can find through JVMArgs ‘gatling.data.graphite.rootPathPrefix’ it is achievable but i have to amend the string (i.e., change “.” to “_” due to limitation in graphite considering “.” as separator for column values. Currently finding no solution to replace string/character in JVMArgs in POM

Thanks