[Svenstaro]

I've recently deep-dived into QEMU performance especially in order to cut down boot/bootstrapping times for quickly running tests and I'd like to share some tricks:

- Templating: https://qemu.readthedocs.io/en/v9.1.0/system/vm-templating.h... - virtio-fs: https://virtio-fs.gitlab.io/ - Overlay storage images: https://wiki.archlinux.org/title/QEMU#Overlay_storage_images

[nijave]

Cloud init will handle unique IDs although might add some boot time

[remram]

You need to get it to re-run, which I'm not sure there is a standard way to do during runtime. Can it even do all its job without a reboot?

[nijave]

Maybe I misunderstood, is this skipping boot as well?

I was thinking the VM would still follow the normal boot process (in which case you can reset cloud init before powering down)

[remram]

Yes they are saving memory state to a file.