Bug 64396 - Incorrectly calculates the response time of parent sampler at the end of the test when using Transaction controller along with timers and duration of test
Summary: Incorrectly calculates the response time of parent sampler at the end of the ...
Status: NEW
Alias: None
Product: JMeter
Classification: Unclassified
Component: Main (show other bugs)
Version: unspecified
Hardware: PC All
: P2 major (vote)
Target Milestone: JMETER_5.3.0
Assignee: JMeter issues mailing list
: 64445 (view as bug list)
Depends on:
Reported: 2020-04-30 06:36 UTC by Deepambika
Modified: 2020-07-26 11:49 UTC (History)
2 users (show)

Contains Sample Script and sample result (15.90 KB, application/x-zip-compressed)
2020-04-30 06:36 UTC, Deepambika

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Description Deepambika 2020-04-30 06:36:04 UTC
Created attachment 37205 [details]
Contains Sample Script and sample result

Analyzed the JMeter calculation with when we run with transaction controller with generated parent sample

Tested with and without Timers in script - (to check the mismatch occurs only when we use timers with a duration)

For example: Tried 5 users infinite loop count and 5 min duration with timer - At the end of the execution alone the child and parent sample response time calculation works weird like showing more response time than the addition of child samples, maybe the reason it adding the think time for further non-executed samples

Tried in a different version of JMeter to confirm the above findings - could observe similar behaviors in the latest version as well

Please find the attached script and sample result. Below is the findings from the attached result,

From the very Last entries with null response message for parent of Jtl could see more response time in parent alone below is one example,

Parent response time = 4710 ms
but its child has = 1711 ms
Comment 1 Philippe Mouawad 2020-04-30 06:59:26 UTC
What has happened is the following:

1588227741936,4710,Parent_GoodReads,200,,Thread Group 1-5,,true,,22767,339,1,1,null,0,0,0
1588227744935,1711,GR - Landing Page,200,OK,Thread Group 1-5,text,true,,22767,339,1,1,https://www.goodreads.com/,1710,0,772

My analysis is that as it is the end of test, in GR - Landing Page:
- GR - Landing Page : 1711ms
- Constant Timer fully running would have exceeded end , so JMeter automatically sets timing so that it does not exceed it: 2999ms
- Search Book did not run

So total is:  4710ms
Which leads to this result.

I cannot tell if we should consider this a bug.

@Team, what do you think ?
Comment 2 Deepambika 2020-04-30 12:11:06 UTC
Thanks for your response,

Here, the constant timer is added only for the first child of Parent_GoodReads i.e, GR-LandingPage. so,my understanding is like, after waiting for 3 sec only the request sent and we got the response in 1711 ms. And more over I haven't enabled the include timer duration in Transaction controller. (Please refer the attached script)

The timer duration has not included for  any of the parent sample entries during or at the start of the test. Could observe this only when the test stops.

My understanding on Calculation of Parent response time - The response time for parent sample is the addition of response times of child samples or if we have one sample the response time of parent should be the response time of single child.

Please correct me if my understanding is wrong/share your inputs on the same.
Comment 3 Philippe Mouawad 2020-07-26 11:49:30 UTC
*** Bug 64445 has been marked as a duplicate of this bug. ***