[Feature] Instance-store-backed AMIs

[johngmyers]

What would you like to be added:

The ability to create instance-store-backed AMIs.

Why is this needed:

We want to avoid the cost of EBS root volumes when using storage-optimized instance types for EKS nodes.

[stevehipwell]

I think this has been released for AL2 & AL2023.

[cartermckinnon]

@stevehipwell this issue is about AMI's that are backed by an instance store (no EBS volume involved): https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/creating-an-ami-instance-store.html

Those are still pretty new and don't have great support in the tooling we use today (and they also have several caveats, such as taking way longer to boot); but they're great in some situations. We'll keep an eye on it.

[stevehipwell]

I think there is some overlapping terminology at play here as Karpenter refers to NVMe drives as instance store volumes.

[bryantbiggs]

instance store volumes is the correct term - some instances have them as additional *disks that can be mounted, but the root volume is still EBS. or you can create an AMI where the root volume is an instance store volume, not EBS