really cool resource for learning but a lot of these have nothing to do with k8s, beyond the company in question having k8s as part of their stack (i'm addressing the possible perception of the post title suggesting k8s horror stories).

A lot of them do have things to do with k8s, though. Admission webhooks, Istio sidecar injection, etc.

The CPU limits = weird latency spikes also shows up a lot there, but it's technically a cgroups problem. (Set GOMAXPROCS=16, set cpu limit to 1, wonder why your program is asleep 15/16th of every cgroups throttling interval. I see that happen to people a lot, the key point being that GOMAXPROCS and the throttling interval are not something they ever manually configured, hence it's surprising how they interact. I ship https://github.com/uber-go/automaxprocs in all of my open source stuff to avoid bug reports about this particular issue. Fun stuff! :)

DNS also makes a regular appearance, and I agree it's not Kubernetes' fault, but on the other hand, people probably just hard-coded service IPs for service discovery before Kubernetes, so DNS issues are a surprise to them. When they type "google.com" into their browser, it works every time, so why wouldn't "service.namespace.svc.cluster.local" work just as well? (I also love the cloud providers' approach to this rough spot -- GKE has a service that exists to scale up kube-dns if you manually scale it down!)

Anyway, it's all good reading. If you don't read this, you are bound to have these things happen to you. Many of these things will happen to you even if you don't use Kubernetes!