Comment by SirMaster
6 days ago
Is it weird that we don't have a way to update the system without rebooting by this day and age?
I think there are things in Linux like live kernel patching (kexec, ksplice), but why by 2026 is this sort of architecture of live system updates not a common or included feature yet?
People hate updates and having to reboot and have downtime right? Security updates to core systems are more important than ever now too. So why hasn't this problem been tackled I wonder?
Wouldn't it be great if our systems could update without us having to reboot and interrupt our workloads?
Some things are easy to live patch, others are complex monsters.
The complex monsters tend to result in corner case considerations like "already open sockets cannot be upgraded but new ones will be" and a massive amount of testing to make sure the convenience saved is more than the risk of inconvenience due to some bug with a complex live patch.
Designing the whole system for live patching from day 1 can reduce the number of complex monsters but it's still more complex, and that's a ton of work (rebuild all or just shipping live patches) that could go into fixing other annoyances/limitations which are even mor inconvenient than rebooting for most users.
The result is some things support them in the most impactful cases, like certain types ofOS kernel updates, but most cases it's better to work on other conveniences instead.
Not only that, my Arch laptop is not even able to continue functioning after full system update without reboot. It unloads nvidia kernel modules crashing newly opened graphical programs.
This might be nvidia driver thing, I've had similar soft-bricking happen on ubuntu as well
Windows does more of this than people notice actually. I was on a system the other day, Server 2016, it had downloaded 2 updates, both system file related, one had installed already and the other one was nagging for a reboot.
Stuff like Windows Defender doesnt even really ask if you want to install the update anymore, it just installs the new virus definitions immediately.
Windows has been gradually "undocking" more and more stuff from the main OS install into separately updatable/restartable/etc components for a while.
Many modern Linux distros encourage restarting too. Atomic distros make restarting to boot into a new image the default, though some have flags to do a "live" update too.
You still have to reboot for things like kernel updates. As far as I'm aware, live patching the kernel is just for security issues.