Kubernetes v1.36 Introduces New Metric for Route Sync in Cloud Controller Manager
Kubernetes version 1.36 introduces a new alpha counter metric, route_controller_route_sync_total, to the Cloud Controller Manager (CCM) route controller. This metric increments each time routes are synchronized with the cloud provider, serving as a critical tool for operators validating the CloudControllerManagerWatchBasedRoutesReconciliation feature gate introduced in Kubernetes v1.35. The feature gate transitions the route controller from a fixed-interval loop to a watch-based approach, triggering reconciliation only when node changes occur. This shift significantly reduces unnecessary API calls to infrastructure providers, alleviating pressure on rate-limited APIs and optimizing quota usage. Operators can perform A/B testing by comparing sync rates with the feature gate disabled versus enabled. In stable clusters with infrequent node changes, enabling the feature results in a dramatic drop in sync counts, as the counter only increases during actual node additions, removals, or updates. This update aims to enhance operational efficiency and resource management for Kubernetes users managing cloud infrastructure. Feedback and further details are available through SIG Cloud Provider channels and KEP-5237.
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Kubernetes v1.36 Introduces New Metric for Route Sync in Cloud Controller Manager
Kubernetes version 1.36 introduces a new alpha counter metric, route_controller_route_sync_total, to the Cloud Controller Manager (CCM) route controller. This metric increments each time routes are synchronized with the cloud provider, serving as a critical tool for operators validating the CloudControllerManagerWatchBasedRoutesReconciliation feature gate introduced in Kubernetes v1.35. The feature gate transitions the route controller from a fixed-interval loop to a watch-based approach, triggering reconciliation only when node changes occur. This shift significantly reduces unnecessary API calls to infrastructure providers, alleviating pressure on rate-limited APIs and optimizing quota usage. Operators can perform A/B testing by comparing sync rates with the feature gate disabled versus enabled. In stable clusters with infrequent node changes, enabling the feature results in a dramatic drop in sync counts, as the counter only increases during actual node additions, removals, or updates. This update aims to enhance operational efficiency and resource management for Kubernetes users managing cloud infrastructure. Feedback and further details are available through SIG Cloud Provider channels and KEP-5237.
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