On: FreeBSD on Firecracker

[dikei]

Kernel boot is plenty fast with real hardware, usually under 1 seconds.

It's everything else that's slow. For example, this is my machine

Startup finished in 14.552s (firmware) + 2.885s (loader) + 741ms (kernel) + 23.116s (initrd) + 11.191s (userspace) = 52.488s

[yencabulator → dikei]

The loader+initrd+userspace time there sounds unreasonable.

I've had libvirt bog standard qemu-kvm (not a microvm) creating a new Ubuntu VM from a disk image & booting to a login prompt in under 10 seconds for more than a decade. This is without fiddling with virtio, doing hardware scans for PCI, VGA, SATA and such, and booting via Grub (your "loader"). Those should be pretty comparable!

[dikei → yencabulator]

Ah, yes, you can ignore the loader + initrd. I'm multi-boot so the loader has 2 seconds timeout, and initrd is waiting for me to input my LUKS password.