Cluster autoscaler

This page shows you how to autoscale your clusters. To learn about how the cluster autoscaler works, refer to Cluster autoscaler .

Cluster autoscaling resizes the number of nodes in a given node pool based on the demands of your workloads. You specify minReplicas and maxReplicas values for each node pool in your cluster.

For an individual node pool, minReplicas must be ≥ 1. However, the sum of the untainted user cluster nodes at any given time must be at least 3. This means the sum of the minReplicas values for all autoscaled node pools, plus the sum of the replicas values for all non-autoscaled node pools, must be at least 3.

Create a user cluster with autoscaling

To create a user cluster with autoscaling, add the autoscaling field to the nodePools section in the user cluster configuration file .

nodePools:
- name: pool‐1
  …
  replicas: 3
  ...
  autoscaling:
    minReplicas: 1
    maxReplicas: 5

This configuration creates a node pool with 3 replicas, and applies autoscaling with the minimum node pool size as 1 and the maximum node pool size as 5.

The minReplicas value must be ≥ 1.

Add a node pool with autoscaling

To add a node pool with autoscaling to an existing cluster:

1. Edit the user cluster configuration file to add a new node pool, and include the autoscaling field. Adapt the values of minReplicas and maxReplicas as needed.

nodePools:
- name: my-new-node-pool
  …
  replicas: 3
  ...
  autoscaling:
    minReplicas: 1
    maxReplicas: 5

1. Run the gkectl update cluster --config <var class="edit">USER_CLUSTER_CONFIG</var> --kubeconfig <var class="edit">ADMIN_CLUSTER_KUBECONFIG</var> command.

Enable an existing node pool for autoscaling

To enable autoscaling for a node pool in an existing cluster:

1. Edit a specific nodePool in the user cluster configuration file, and include the autoscaling field. Adapt the values of minReplicas and maxReplicas as needed.

   nodePools: 
    
   name: my-existing-node-pool
   …
   replicas: 3
   ...
   autoscaling:
   minReplicas: 1
   maxReplicas: 5