If it was kernel level only, maybe. But why does windows seem like it needs to restart after every little update?
It's also good since you can't swap out the kernel without rebooting.
I assume Microsoft took the same approach, just replace everything offline then reboot into a fully up-to-date system without any chance of things in RAM still being outdated.
Yeah you can. Ksplice.com We got bought by Oracle so it's in their ecosystem but the technology exists.