Prepare to enable Linux pressure stall information on Red Hat OpenShift

This article discusses how to enable Linux pressure stall information (PSI) monitoring in Red Hat OpenShift 4.21, detailing its benefits for monitoring resource contention in clusters. It presents performance evaluation results indicating that enabling PSI significantly increases memory usage for Prometheus pods while having no observed impact on kubelet CPU or memory usage. The article concludes with recommendations for planning resources and monitoring usage when implementing PSI in production.