[systemd-devel] [systemd-commits] units/basic.target units/poweroff.target units/reboot.target

[Simon McVittie]

On 06/11/14 14:16, Zbigniew Jędrzejewski-Szmek wrote:
> What matters is how it is all arranged:
> 
> - if there's a job that does stuff, and then calls reboot or shutdown
> - a hook into the shutdown or reboot target does some work

unattended-upgrades is currently the latter: the user shuts down (or is
reminded to shut down by an update notification), and
unattended-upgrades runs as a side-effect.

This is an optional (non-default) configuration of an optional package,
not core Debian/Ubuntu functionality; so it doesn't necessarily have to
be like this forever, it could be modified to tell systemd "I'm still
shutting down, continue to wait" periodically, it could be modified to
use "reboot into a special mode, install, then reboot again" logic under
systemd if that's something you already have, and, worst-case, it could
install a drop-in to override the timeout.

The default configuration is currently to perform the upgrades in-place
and prompt the user to reboot when convenient, just like a manual
apt/zypp/etc. run would.

I have worked on improving u-u's upgrade-during-shutdown mode for
SteamOS, where it is actively used in that mode (SteamOS doesn't use
systemd yet, as far as I know). With my patchset, it pre-downloads all
necessary packages and performs a pre-prepared transaction during
shutdown. Without my patchset, it downloads stuff during shutdown, which
seemed rather more precarious than anyone wants.

    S