When you select instance types and define vCPU or memory ranges for a VNG, Ocean helps by:

• Filtering out instance types that do not meet your resource requirements.
• Adjusting minimum and maximum ranges so they match the actual capabilities of the instance types you selected.

Example

If you whitelist T2 and T3 instance families with:

• CPU range: 1–2
• Maximum memory: 16 GB

After applying the settings and revisiting the configuration, you may notice the maximum memory automatically adjusts to 8 GB because 8 GB is the highest memory available for the instance types you chose.

Instance types and Ocean selection behavior

One of Ocean’s most powerful features is running your workloads on Spot Instances for cost savings. However, Spot Instances can be interrupted by your cloud provider with up to two minutes’ notice. When this happens, Ocean will seamlessly replace the impacted instance with another available Spot Instance or fall back to On-Demand if required.

To ensure Ocean has enough flexibility to make these replacements, we recommend that you select as many instance types and sizes as possible. Having a broad Spot market selection gives Ocean greater ability to pick the right instance, maintain stability, and optimize costs.

By default:

• All instance types supported by your selected AMI are preselected.

• Ocean automatically chooses the optimal instance type based on pending pods, workload requirements, and constraints.

• If you select an ARM-based AMI (such as Graviton), Intel x86 instance types are automatically deselected or disabled.

How you can allowlist instance types

If you want more control over which instance types Ocean uses, you can allowlist instance types at the VNG level in two ways:

• Manual approach: Expand any category (for example, Compute Optimized) and select or deselect the instance types you want for your workloads.

• Advanced approach: Apply filters based on attributes such as vCPU, memory, or GPU cores. Ocean will then automatically allowlist instance types that meet your requirements.

Example of advanced filtering:
If your Customer Choice Analysis service needs GPU cores, you can specify GPU requirements in the advanced filter. Ocean will automatically allowlist only instance types with GPUs, saving you time compared to manually selecting them.

For more details on filters, visit Machine Types.

Important note:
When creating an Ocean Cluster, the instance types you select at the cluster level become the base set. Any instance type selection you make for a VNG is a subset of this list. If you did not select a family like C1 at the cluster level, it will not be available for selection in the VNG and will appear grayed out.

Outcome

By understanding how Ocean calculates and adjusts instance types and resource ranges, you can fine-tune your configuration to balance workload requirements with optimal pricing strategies.