[jwkane]

Nginx-ingress (the free version) does a reload when pods are added/removed. I would expect to see latency spikes. As I understand it the paid nginx-ingress can do these reconfigs on-the-fly. If you have pods adding/removing frequently, like maybe from "We then scale up the backend service to four pods and then scale it back down to three pods every thirty seconds", this is what you see. The more interesting question is if that is a realistic expectation for your workload. Unless you are doing aggressive auto-scaling pods can be very stable, only add/removing during upgrades.

[rdli]

This is a good point. I think an interesting test would be to add multiple services, and see if scaling up/down a single service affects latency to other services.