HM module: bind mounts not working with HM xsession about impermanence HOT 5 CLOSED

So I just did a quick test and did some reading on systemd.

For me changing the PartOf of the bind mount units to default.target or removing it alltogether seems to work just fine. On login the services get started and when I close the last user session they get stopped and the bind mounts get unmounted. This works no matter what way I login (graphical, console or remote).

Since I don't quite understand why PartOf=graphical-session-pre.target is there in the first place I have to ask what the intention of that is? Is this needed to make some part of Home Manager (switching) work correctly?

from impermanence.

The reasoning behind PartOf=graphical-session-pre.target is to have them start as early as possible and before the rest of the graphical user session is started. The user could, for example, have autostart programs which rely on directories being bind mounted. On my installations, which don't use the home-manager xsession, this works fine. I don't really see a reason why the graphical-session-pre.target should be stopped when the session has started; in fact it seems to contradict the upstream description of its use.

@rycee Do you know if there's a reason graphical-session-pre.target is stopped here?

from impermanence.

From what I understand making the unit PartOf=graphical-session-pre.target is not the correct way of achieving that behavior since PartOf only affects the unit when the given units are stopped or restarted.

Here's what systemd.unit(5) has to say:

PartOf=
Configures dependencies similar to Requires=, but limited to stopping and restarting of units. When systemd stops or restarts the units listed here, the action is propagated to this unit. Note that this is a one-way dependency — changes to this unit do not affect the listed units.

Also I don't feel like impermanence should depend on a graphical-session at all.
On the other hand I don't see any targets in the various systemd manpages that we could attach to to make sure the bind mount units get started before any other units that might depend on the mounts being present already.
I'm running impermanence with the bind mount units just WantedBy=default.target for a week now without any issues though.

from impermanence.

Oh, right, I got it confused with Requires - they currently start because WantedBy=default.target gets added by default. The correct option would probably be WantedBy=graphical-session-pre.target, though.

from impermanence.

Um, wait, no Install.WantedBy = [ "default.target" ] is in the definition of the unit, so never mind. As it's been working fine so far I guess we could just remove the PartOf and keep the WantedBy as is for now; that way it won't depend on a graphical session either.

from impermanence.