Node group autoscaling in Managed Service for Kubernetes
The cluster autoscaler resizes the node group based on resource requests for the pods running on the nodes of that group.
How the autoscaler works
You specify the minimum and maximum size of the node group, and the Kubernetes cluster periodically checks the status of the pods and nodes:
- If the pods can't be scheduled onto the existing nodes due to insufficient resources (vCPU, RAM), the number of nodes in the group gradually increases to the maximum specified.
- If the load on the nodes is insufficient and all pods can be scheduled onto fewer nodes in the group, the number of nodes gradually decreases to the minimum specified.
Warning
You can resize an autoscaling group using Kubernetes cluster-autoscaler
- If you can distribute the load in a cluster to a smaller number of nodes, but you cannot evict pods from the nodes for some reason, the number of nodes in a group will not decrease.
- The actual number of nodes in a group may be below the minimum size of a node group. This may occur if:
- An autoscaled group resized up from its minimum size after being created.
- Actual cluster load does not require more nodes than the cluster currently has.
Note
When calculating the current limits and quotas
The node group autoscaler is different from Horizontal Pod Autoscaler