Cluster Autoscaler threshold tuning in Gardener lacks documented guidance for workload patterns

Cluster Autoscaler Default Threshold Behavior

Gardener supports cluster autoscaling through the Cluster Autoscaler addon, which can be enabled in the Cluster spec. The addon uses provider-specific default configurations that may not align with a cluster's actual workload characteristics.

The decision to enable or disable the autoscaler rests with the cluster administrator, yet the documentation does not provide clear guidance on optimal threshold settings for different workload patterns. There is no automatic health check for the autoscaler; users must monitor its logs and metrics to verify proper operation.

This creates an unresolved question about how to determine appropriate thresholds for scale-up and scale-down operations, particularly when workloads have variable or unpredictable resource demands.

Specific Questions

• What are the recommended threshold values for the Cluster Autoscaler when workloads exhibit periodic or bursty patterns?
• How can administrators validate that autoscaler thresholds are appropriately configured without causing excessive node churn?