Vertical Pod Autoscaler

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Coverage Matrix

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Vertical Pod Autoscaler Overview

Vertical Pod Autoscaler (VPA) automatically adjusts the CPU and memory requests of Kubernetes workloads based on real-time usage patterns. It analyzes historical metrics to right-size resources, reducing the risk of OOM kills and preventing excessive over-provisioning. By dynamically evicting and recreating pods with updated resource requests, it helps maintain efficient cluster utilization. Since VPA acts as an admission webhook, it integrates seamlessly with the Kubernetes control plane while requiring careful coordination if other autoscalers are in use. Overall, VPA provides a hands-off way to continuously match resource consumption to actual demand.

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Chkk Coverage

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Curated Release Notes

Chkk continuously monitors the official release notes and changelogs for the Vertical Pod Autoscaler. It distills these into actionable insights—highlighting any breaking changes, deprecated APIs/CRDs, and important operational impacts in each release. Instead of wading through raw upstream notes, you get a curated summary focused on what matters for your clusters. For example, if a new VPA version removes a beta API or changes how recommendations are calculated, Chkk will flag this prominently so you can prepare in advance. This saves time and ensures you don’t miss critical changes when planning an upgrade.

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Preflight & Postflight Checks

Upgrading VPA without proper checks can lead to misconfigurations or downtime. Chkk performs preflight validations to ensure your environment is ready for the new VPA version. These preflight checks catch issues like missing Metrics Server, outdated VPA CRDs, or insufficient cluster resources, preventing a failed rollout due to configuration mismatches. After the upgrade, Chkk runs postflight checks to confirm everything is working correctly. It ensures the new VPA components are running healthy and that your workloads are receiving recommendations as expected. Together, the pre- and postflight checks provide a safety net around the upgrade, ensuring any problems are identified and addressed either before changes are applied or immediately after the new VPA is in place.

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Version Recommendations

Chkk’s platform keeps track of VPA release milestones and end-of-life (EOL) information. It will proactively alert you if the VPA version you’re running is approaching EOL or has become outdated. Chkk suggests safe upgrade paths to a supported version. These version recommendations are tailored to your environment - for example, if you’re on a legacy 0.x or 1.x VPA release, Chkk will identify a stable newer release that is compatible with your current Kubernetes cluster version and VPA configuration. Chkk helps you plan upgrades ahead of time so you’re never caught running an unsupported VPA.

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Upgrade Templates

Upgrading the Vertical Pod Autoscaler can involve multiple steps (updating CRDs, deploying new controller components) in a live cluster, so Chkk provides Upgrade Templates for two strategies: in-place upgrades and blue-green (canary) upgrades. The in-place template guides you through backing up current VPA configurations, applying new CRDs, and updating the recommender, updater, and admission webhook with safety checks and rollback points to ensure high availability. The blue-green template runs a new VPA version in parallel (for example, in a separate namespace), letting you gradually migrate VPA objects and observe behavior on subsets of workloads. It ensures only one VPA actively adjusts a given workload at a time and offers a clear path to fully cut over or roll back if issues arise.

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Preverification

One of Chkk’s most powerful capabilities is preverification - essentially a dry-run of your VPA upgrade in a controlled environment. Before you ever apply changes to your production cluster, Chkk can simulate the upgrade in an isolated cluster that mirrors your production setup. In this preverification phase, Chkk deploys the target version of the Vertical Pod Autoscaler along with your current VPA configuration to see how they interact. This process can catch a range of potential issues early. Chkk will report any detected anomalies during this dry-run. This feature gives platform engineers a chance to test-drive the VPA upgrade safely, ensuring that by the time you perform the real upgrade, you’ve already resolved the major risks in a sandbox.

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Supported Packages

It has built-in support for VPA deployments via Helm charts, Kustomize overlays, plain Kubernetes YAML manifests, or add-on managers. Upon connecting to your cluster, Chkk auto-detects your current VPA version and manifest source. It highlights changes in Helm chart values, provides manifest patches or overlay updates, and verifies operator version requirements while preserving custom configurations, images, and private registry references. Even if you use a custom-built VPA image, Chkk can still track version parity with the upstream project.

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Common Operational Considerations

• Coordinate VPA with HPA carefully - Avoid running both on the same resource metric, as VPA adjusts CPU/memory requests while HPA scales replicas. If both target CPU, VPA changes may confuse HPA’s calculations, causing oscillations; isolate metrics or use custom ones.
• Expect and manage pod restarts - VPA updates require pod restarts, making it a disruptive event. Use Pod Disruption Budgets (PDBs) and rollout strategies to prevent downtime, ensuring pods don’t restart simultaneously or move unpredictably between nodes.
• Ensure cluster capacity for scaling - VPA may suggest resources beyond what the cluster can provide, causing pods to remain unschedulable. Use Cluster Autoscaler with VPA and enforce resource limits to prevent excessive recommendations that outpace hardware.
• Update CRDs and handle API deprecations - VPA CRDs and API versions evolve, so always upgrade them before updating VPA. Failure to migrate deprecated API versions can break VPA functionality; review release notes and apply the latest manifests to avoid issues.
• Mind admission webhook interactions - VPA acts as an admission controller, and conflicts can arise with other webhooks like OPA or PSPs. Verify that VPA’s webhook is still applying resource updates correctly after upgrades or adding new admission controllers.

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Additional Resources

• Vertical Pod Autoscaler Documentation
• Vertical Pod Autoscaler Releases