Cluster Auto-Scaling

Auto-scale container level

• Horizontal Pod Autoscaler (abbreviated as HPA) automatically updates workload resources (such as Deployment or StatefulSet), with the purpose of automatically scaling workload resources to match application demand. Basically, when the workload of an application on Kubernetes increases, HPA will deploy more Pods to meet the resource demand. If the load decreases and the number of Pods exceeds the configured minimum, HPA will reduce the workload resource (Deployment, StatefulSet, or other similar resources), i.e., reduce the number of Pods again. HPA for GPU uses DCGM's custom metrics to monitor and scale Pods based on the workload of GPU-using applications.

• To configure HPA for GPU-based applications, refer to the following configuration:

apiVersion: autoscaling/v2beta2 

kind: HorizontalPodAutoscaler 

metadata: 

 name: my-gpu-app 

spec: 

 maxReplicas: 3  # Update this accordingly 

 minReplicas: 1 

 scaleTargetRef: 

   apiVersion: apps/v1beta1 

   kind: Deployment 

   name: my-gpu-app # Add label from Deployment we need to autoscale 

 metrics: 

 - type: Pods  # scale pod based on gpu 

   pods: 

     metric: 

       name: DCGM_FI_PROF_GR_ENGINE_ACTIVE # Add the DCGM metric here accordingly 

     target: 

       type: AverageValue 

       averageValue: 0.8 # Set the threshold value as per the requirement 

• Check if HPA has started the GPU-based application using the following command:

  

Auto-scale Node level

Like regular Cluster Auto-scale, the Kubernetes cluster will automatically scale worker nodes in a worker group up or down based on GPU usage requirements: it will automatically scale up new workers in a worker group if the application running on that worker group is not getting enough resources (GPU) from the worker nodes in that pool.

At that point, pods that were pending due to insufficient node resources will be served by the new worker nodes after scaling up. The Cluster Autoscale feature also automatically deletes nodes that do not use enough utilization (default is 50%) of that node.

Configuring the number of worker group nodes is defined on the FPT Cloud Portal as shown below:

Enabling Cluster Auto-Scaling

Step 1: Select [Containers] > [Kubernetes] from the menu to display the Kubernetes Management page. Select the cluster for which you want to enable the cluster auto-scaling feature.

Step 2: Select Node Pools > Edit Workers.

Step 3: Adjust the minimum and maximum number of workers according to the sizing selected by the user.

Note: If the maximum number of workers is greater than the minimum number, the cluster auto-scaling feature is automatically enabled.

Step 4: Review the information and select [Save] to enable the cluster auto-scaling feature.

Disabling the Cluster Auto-Scaling

Step 1: Select Kubernetes from the menu to display the Kubernetes Management page. Select the cluster for which you want to disable the cluster auto-scaling feature.

Step 2: Select Nodes Pool > Edit workers.

Step 3: Adjust the minimum and maximum worker counts to the same number.

Note: When the minimum and maximum worker counts in the worker pool are the same, the cluster's auto-scaling feature is automatically disabled.

Step 4: Review the information and select "Save".

Modifying Cluster Auto-Scaling Settings

Step 1: Select [Containers] > [Kubernetes] from the menu to display the Kubernetes Management page. Select the cluster for which you want to customize the cluster auto-scaling settings.

Step 2: Select Nodes Pool > Edit workers.

Step 3: Adjust the number of workers according to your usage needs.

Step 4: Review the information and select "Save".