As I understand it, updating to a new kernel (with the normal `linux-image...` package, not by rolling my own) requires a server restart.

However, one of our servers (Ubuntu 10.04) is running several extensive `screen` sessions. Restarting kills those which is always a major hassle to their owners (mostly because of lost session histories).

What should I do? I see several possibilites:

* Not doing anything, that is update only non-kernel packages (perhaps use apt-pinning?)
* Update the kernel, but not restart. (Is that smart? I seem to remember there might be some problems with loading kernel modules.)
* Updating the kernel and restarting.
	+ Is there perhaps some way to preserve the `screen` sessions?

I guess it ultimately boils down to this question:
**How important is it to update the kernel?**

I posted this question here instead of askubuntu.com as I think this is not an Ubuntu-specific issue though this server is running Ubuntu.