Using Spot Instances

When creating a cluster you can optionally use spot instances as compute nodes. The following table describes supported use cases:

Use Case Parameters Implications
I don't want to use spot instances, but I want to create compute nodes using on-demand EC2 instances.

Compute Instance Count: 1 or larger

Do not check Use Spot Instances

Your cluster will be created using regular on-demand instances as compute nodes.

If you decide to scale up by adding compute nodes, on-demand EC2 instances will be used to create additional nodes.

I want to create compute nodes using spot instances when creating my cluster.

Compute Instance Count: 1 or larger

Check Use Spot Instances

If spot instances are not available right away, creating a cluster will take longer than usual.

Once someone outbids you, the spot instances will be taken away, removing compute nodes from the cluster.

If you decide to add compute nodes later, spot instances will be used. The price bid that you specified when creating the cluster will be used.

I don't want to create any compute nodes when creating my cluster, but I may want to add compute nodes using spot instances later.

Compute Instance Count: 0

Check Use Spot Instances

If you decide to add compute nodes later, spot instances will be used. The price bid that you specified when creating the cluster will be used.

If the bid price is too low at the time when you want to add new compute nodes, you can 1) create a new cluster and enter a new bid price, or 2) add additional worker nodes rather than compute nodes.

I don't want to use compute nodes.

Compute Instance Count: 0

Do not check Use Spot Instances

Your cluster will be created without adding any compute nodes.

If you decide to add compute nodes, on-demand EC2 instances will be used to create additional nodes.

After creating a cluster, you can view your bid price in the cluster details. You can also view your spot instance requests on the EC2 dashboard:

  1. Navigate to the EC2 dashboard in your selected region.
  2. Navigate to INSTANCES > Spot Requests.

For more information on spot instances, refer to AWS documentation.