
Haowei Chen developed and stabilized Pressure Stall Information (PSI) observability features across the Kubernetes stack, focusing on resource contention visibility and proactive capacity planning. Working in the kubernetes/kubernetes and kubernetes/enhancements repositories, Haowei designed and implemented API surfaces, feature gates, and end-to-end monitoring for PSI metrics using Go, Kubernetes, and Protobuf. He advanced PSI-based node conditions through phased rollouts and robust documentation, aligning with Kubernetes release cycles. Haowei also improved test reliability by refining CPU stress tests and enhancing test infrastructure, reducing CI flakiness. His work demonstrated depth in backend development, system monitoring, and technical writing within large-scale cloud environments.

In August 2025, focused on stabilizing the Kubernetes test suite by delivering a CPU stress test reliability improvement. Implemented a 500m CPU limit for the cpu-stress-pod, ensuring deterministic CPU pressure during tests, reducing flaky CI failures, and accelerating feedback loops. Change was committed to kubernetes/kubernetes (ea9d7ff8656db94393d16645fdc10402b969e99c).
In August 2025, focused on stabilizing the Kubernetes test suite by delivering a CPU stress test reliability improvement. Implemented a 500m CPU limit for the cpu-stress-pod, ensuring deterministic CPU pressure during tests, reducing flaky CI failures, and accelerating feedback loops. Change was committed to kubernetes/kubernetes (ea9d7ff8656db94393d16645fdc10402b969e99c).
July 2025 monthly summary: Delivered PSI-related features in the kubernetes/kubernetes repo focused on observability and reliability of node resource pressure metrics. Major bugs fixed: none reported this month. Overall impact: promoted Kubelet PSI metrics exposure to beta in Kubernetes 1.34, expanded end-to-end testing for CPU/Memory/I/O pressure, and strengthened test infrastructure with feature flags and cgroup v2 compatibility checks. Technologies/skills demonstrated include Go, Kubernetes feature gates, end-to-end testing, and handling of cgroup v2 awareness.
July 2025 monthly summary: Delivered PSI-related features in the kubernetes/kubernetes repo focused on observability and reliability of node resource pressure metrics. Major bugs fixed: none reported this month. Overall impact: promoted Kubelet PSI metrics exposure to beta in Kubernetes 1.34, expanded end-to-end testing for CPU/Memory/I/O pressure, and strengthened test infrastructure with feature flags and cgroup v2 compatibility checks. Technologies/skills demonstrated include Go, Kubernetes feature gates, end-to-end testing, and handling of cgroup v2 awareness.
June 2025 monthly summary focusing on delivering the PSI-based Node Conditions and Metrics rollout (KEP-4205) in kubernetes/enhancements. Central achievements included advancing Phase 2 readiness, establishing governance for PSI-based node conditions, and aligning KEP updates with Beta requirements and 1.34 timelines. The work created a clear phased rollout path with phase separation and robust documentation to reduce rollout risk and enable cross-team coordination. Minor documentation fixes and clarifications improved maintainability and reviewer efficiency, while monitoring and version-skew details were refined to support safe upgrades and observability.
June 2025 monthly summary focusing on delivering the PSI-based Node Conditions and Metrics rollout (KEP-4205) in kubernetes/enhancements. Central achievements included advancing Phase 2 readiness, establishing governance for PSI-based node conditions, and aligning KEP updates with Beta requirements and 1.34 timelines. The work created a clear phased rollout path with phase separation and robust documentation to reduce rollout risk and enable cross-team coordination. Minor documentation fixes and clarifications improved maintainability and reviewer efficiency, while monitoring and version-skew details were refined to support safe upgrades and observability.
March 2025: Delivered cross-stack PSI observability across Kubernetes (Kubelet, CRI, and monitoring) to improve resource contention visibility. Implemented alpha Kubelet PSI feature gate, API surface for PSI metrics, exposure of PSI metrics from cadvisor to the summary API and Prometheus, CRI API extension for PSI, and CRI stats provider integration, reinforced by unit and end-to-end tests. This enables end-to-end PSI monitoring for nodes, pods, containers, and sandboxes, driving proactive capacity planning, faster troubleshooting, and data-driven scheduling decisions.
March 2025: Delivered cross-stack PSI observability across Kubernetes (Kubelet, CRI, and monitoring) to improve resource contention visibility. Implemented alpha Kubelet PSI feature gate, API surface for PSI metrics, exposure of PSI metrics from cadvisor to the summary API and Prometheus, CRI API extension for PSI, and CRI stats provider integration, reinforced by unit and end-to-end tests. This enables end-to-end PSI monitoring for nodes, pods, containers, and sandboxes, driving proactive capacity planning, faster troubleshooting, and data-driven scheduling decisions.
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