DevConf.CZ 2025

Josephine Pfeiffer

Josephine is a consultant specializing in developer productivity and infrastructure. She has worked for enterprises, SMEs, and startups in roles spanning platform engineering, DevOps, Site Reliability Engineering, and technology management.

She is an active open-source contributor to Kubernetes-related projects such as Backstage and Kube-burner. Josephine has shared her expertise at several conferences, including BSides Bristol, Kubernetes Community Days Zurich Rejects, and Uphill Conf.


Company or affiliation

Red Hat

Job title

Senior Consultant


Session

06-14
11:00
35min
Beyond CAS: Why the world needs another Kubernetes Cluster Autoscaler
Josephine Pfeiffer

Kubernetes' Cluster Autoscaler (CAS) has been the standard for dynamic scaling, but it suffers from limitations that hamper its performance in some scenarios.
This talk introduces Karpenter, a modern alternative designed for real-time, workload-specific node provisioning. We will present the development of a custom IBM Cloud Karpenter provider, highlighting its architecture, implementation challenges, and experimental results.
Using the scientific method to benchmark performance, we compare scaling efficiency, cost savings, and resource utilization of CAS and Karpenter across AWS and IBM Cloud in different scenarios.
This session offers practical insights for cloud architects and Kubernetes practitioners looking to optimize autoscaling in cloud-native environments.

Cloud, Hybrid Cloud, and Hyperscale Infrastructure
E112 (capacity 156)