[vmg12]

Does it only work with that specific version of firecracker and only with vms with 1 vcpu?

More than the sub ms startup time the 258kb of ram per VM is huge.

[adammiribyan]

1 vCPU per fork currently. Multi-vCPU is doable (per-vCPU state restore in a loop) but would multiply fork time.

On Firecracker version: tested with v1.12, but the vmstate parser auto-detects offsets rather than hardcoding them, so it should work across versions.