JMeter Graph - Why Response Times Lower When There are More Threads

0
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I am doing the performance testing using Apache JMeter 5.0 with following thread group settings: Number of Threads (users) = 100

Ramp-Up Period (in seconds) = 5

Loop Count = 1

However, I noticed that the response time is getting lower when the number of threads are increasing.

Can help to explain or guide on what happening here?

1
jmeterjmeter-plugins

1 Answers

0
votes

There could be multiple reasons for this, straight-ahead I can assume following ones:

  1. You're firing the same requests and your application caches the response and returns it directly from memory or disk instead of processing. If this is the case - consider parameterizing your JMeter test in order to send different or unique requests.
  2. Your test duration is too low and application cannot "warm-up" immediately. Consider longer ramp-up period
  3. Your test duration is too low so you never reach 100 concurrent users, try setting Loop Count to "Forever" and limit your test duration via Scheduler section of the Thread Group or using Runtime Controller
  4. Your application is capable of auto-scaling and it automatically gets higher virtual hardware specifications or extra cluster nodes via i.e. k8s. Consider setting up monitoring what happens on the application under test side using i.e. JMeter PerfMon Plugin