Only the first request-response sampler's result works well

[Former user]

Hi, I have set up several WebSocket request-response samplers, but only the result in the first WebSocket after 'Open Connection' comes out correctly. So I am doing testing with only one request-response sampler. Any help you can provide would be much appreciated.

[Peter Doornbosch]

I looked in my crystal ball, but i don’t see anything.

You’re asking me: “he, it works the first time and not the second time, how come?”

How do you think my brain works, that i could answer such a question? I can tell you, this plugin is used by a lot of people, and for most, it works all the time. The second and the third and the forth, etc.

So maybe you try a little harder to explain your problem. What kind of information you think i would need to help you with your problem?

[Soo]

I'm really sorry for my poor explanation. Didn't you see images I attached? I’m not good at English but let me explain it again.

I’ve set up multiple request-response samplers by using this plugin. However, looking at the test results, only the results of Open Connection and the first sampler seem to come out normally. Am I using it wrong? I’ve attached the JMeter setup screen and a screenshot of the result.

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When I setup only one request-response sampler, The result looks good as shown in the image below.

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[Peter Doornbosch]

What are the results of the second sampler (the first one that fails)? In the “View Results Tree”, usually some information can be found why the sampler failed. Knowing why the sampler failed would be a good first step to analyse the problem.

[Soo]

Thanks Peter,

Don't mind the fail. It happened with the timeout set up for the test. The problem is that the response time of all other samplers after the first sampler is 0 or 1 or weird. So now I’m testing with only one request-response sampler.

[Peter Doornbosch]

So your issue is solved now? Then i’ll close the ticket.

[Soo]

It’s not solved. I think multiple request-response samplers are working weird. I’ll test with the other WebSocket sevice. you can close the ticket.

[Peter Doornbosch]

I can help if you let me know what exactly the result is that the second sampler is reporting and if you show how it is configured (how the timeout is set).

What also could help: enable debug logging (see readme) and send me the relevant logging that will appear in jmeter.log; then i might be able to see what the second sampler is doing.

[Soo]

I’ll try again with debug logging tomorrow.

Many thanks.

[Soo]

I did two tests. Two samplers were used for the first test, and if you look at the csv file (result_1.csv), you can see that the elapsed time of WebSocket2 is very short. Even 0s and 1s are mostly. The second test is to run one sampler several times using the Loop Controller, but the results are similar (result_2.csv).
(you can download log and result files in here)

I want to test one thread doing multiple actions vis WebSocket request-response samplers after open connection, but I can't find a way.
You can test this out, or close the ticket if you think it's not a bug.

Thank you for the support!

[Peter Doornbosch]

I still wonder why you did not have a single look at the sampler result for the sampler that fails. That would have told us immediately what is going on.

Anyway, the “problem” with the zero response times, is that your server is sending fragmented frames. The continuation frames are already received (in the tcp receive buffer) when the second sampler is firing.

I still don’t know what exactly is your problem. It seems that the outcomes is different from your expectation, but for me it is not clear what your expectations are.

If the problem is that there are sampling errors, than, as i said before, go the “view results tree” and select the first sampler that is in error. Then at the right there are several tabs, e.q. “sampler result” and see what it is telling you what the error is.

Your english is not the problem, you’re too vague about what, in your perception, is going wrong.

[Soo]

When I using an actual application, the response time of the first request could be 1.3 second and the response time of the second request could be 1.1 seconds after connecting to the WebSocket. I just wanted results like that not 0 response time.

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Let me take a look at the fragmented frame. Now it's okay to close the ticket.
Thank you for your support!

[Peter Doornbosch]

Check the readme for explanation how the plugin does (not) handle fragmentation.