What people aren't getting with `firecracker` is utilization. Don't get me wrong, `firecracker` is great software and it's what I'm using for lightweight virtualization, but workloads are really bursty over really short periods of time now, even with the snapshot and restore that you can get if you're willing to hack on `firecracker` substantially, you hit walls where it's like, this is too much against the grain, this thing wasn't designed to bounce from 1 core to 32 to 8 to 16 to 4 to 32 to 1 seamlessly, and that's what it takes to get extreme utilization even with extremely good ML on the prediction.

I am quite sure I'm not the only person working on post-firecracker KVM.

I designed my take to basically eliminate the concept of vm being a rigid box of cpu/memory with CPU oversubscription and virtio-ballooning on memory + sparse ext4.

That way it can be elastic in CPU, memory and somewhat disk.

How far are you on your take?