kubernetes ingres-nginx config change -> slow response time

[Steven1979]

Hi,

We find in two kubernetes clusters that any ingress nginx config changes are made (new backend, log modify...), the result is that the the proxy response time will be bad, slow, as long as we do not delete the pods. After restarting the ingress-nginx-controller pods everything is ok.

ingress-nginx-4.0.17
k8s:  v1.21.6+2.el7

Idea?

[Nikoolayy1]

There are a lot of of articles about tracing the traffic in nginx:

https://www.nginx.com/blog/application-tracing-nginx-plus/

https://www.nginx.com/blog/opentracing-nginx-plus/

https://docs.nginx.com/nginx-ingress-controller/troubleshooting/troubleshoot-ingress-controller/

Also you can check the release notes for known issues and fixes and better run the latest nginx version:

https://docs.nginx.com/nginx-ingress-controller/releases/#nginx-ingress-controller-222

[Patrik_Jonsson]

Probably a silly question, but have you checked the logs of the ingress pods?
Also, have you checked any performance graphs in Prometheus to check for ie. CPU throttling?

[Nikoolayy1]

If you managed to get the needed answers, please flag the question as answered.