In-Place Rightsizing

Komodor supports in-place rightsizing for Kubernetes clusters running v1.33 or higher. 

This capability allows updating pod CPU and memory requests without restarting running pods, ensuring faster optimization cycles and higher realized savings.

Prerequisites

In-place rightsizing is available only when:

• The cluster runs Kubernetes v1.33 or higher.

• The feature gate InPlacePodVerticalScaling is enabled.

• Komodor agent version is 0.2.174 or higer

If these conditions aren’t met, the Apply Immediately option in the policy settings will be disabled, and rightsizing will continue to occur only when pods are created or restarted.

How it works

1. When Komodor generates new rightsizing recommendations, it evaluates each workload and determines the appropriate apply protocol based on the workload’s configuration and whether it meets Kubernetes requirements for in-place rightsizing
2. Limits may be adjusted only in cases of under-provisioned workloads (rightsizing up), and according to the policy configuration settings

3. Apply Protocols

The rightsizing apply protocol determines when recommendations are enforced:

• Apply Immediately (In-Place)
  • Applies changes to running pods via Kubernetes PATCH
  • Also applies on future pod admissions
• On Pod Creation/Restart
  • Applies recommendations only when a pod is created or restarted

Apply Immediately is the default when supported and is marked as Recommended.

Fallback Behavior

If any validation fails at runtime (cluster, workload, or API rejection):

• The system safely falls back to on-create rightsizing
• No pod restarts are triggered

K8s In-Place Rightsizing Limitations

Even if a cluster is eligible, not all workloads support in-place resizing.

• QoS preservation: the initial QoS must be maintained 
• Operating system: Windows pods aren't supported
• Container types: Init and ephemeral containers aren't supported

Refer to the official Kubernetes documentation for detailed information about in-place rightsizing limitations.