Getting 'Timeout' issue while loading more than 2000 VUs

While running load test with more than 2000 concurrent Users in K6 ,We observed that we are facing continues ‘Timeout’ issue for the Token API(from which the bearer token is fetched and passed to Successive Apis)

We also added time out of 360 sec in param still we are getting same issue.
Also observed Token API Host where CPU utilisation is not much more than 30%.

Error:-
time=“2023-04-19T11:47:10Z” level=warning msg=“Request Failed” error=“URL/token": dial: i/o timeout”

Hi @Pranav

Welcome to the community forum :wave:

I would need a bit more context to help you figure this out. When you say the “Token API Host” I’m missing context. Are you testing and endpoint that requires a bearer token, that you previously get for each VU, and that previous step is what fails?

It does seem from what you describe that your system under test (SUT) might have issue with the load when you reach 2000 concurrent users. However, without more information and context I can’t say for sure.

Can you share the (sanitized) script, and the complete output of the test? That might help us have some context.

It can be useful to read the guide on how to run large tests: Running large tests as the bottleneck can be either at the SUT side or on the load generator.

Cheers!