Kube-state-metrics exposes Prometheus metrics of the state of a given Kubernetes cluster. The project uses the standard Prometheus client Golang library, which is not optimized for the very specific use case of kube-state-metrics.
This talk covers different optimizations like metric caching and improved text marshaling dividing CPU usage by a factor of 6 and memory and response time by a factor of 3 through introducing an intelligent Prometheus metric cache in the code hot path and optimizing memory allocations during response generation.