[systemd-devel] How to find out the processes systemd-shutdown is waiting for?

[Andrei Borzenkov]

On 08.03.2022 18:20, Manuel Wagesreither wrote:
> Hi all,
> 
> Am Do, 3. Mär 2022, um 19:02, schrieb Lennart Poettering:
>> On Mi, 02.03.22 17:50, Lennart Poettering (lennart at poettering.net) wrote:
>>
>>> That said, we could certainly show both the comm field and the PID of
>>> the offending processes. I am prepping a patch for that.
>>
>> See: https://github.com/systemd/systemd/pull/22655
>>
>> Lennart
> 
> now that is some service. Thanks for looking into this that quickly!
> 
> I think we solved our issues, and it seems they were not related to docker at all. The mistake was on our side.
> 
> We were using the PowerOff() method from org.freedesktop.systemd1.Manager [1], which the manpage advices against. When using PowerOff() from org.freedesktop.login1.Manager, which as per the manpage is the preferred way to trigger a shutdown from GUI, things seem to work okay.
> 
> That is, this shows the described issues:
> ```
> dbus-send --system --print-reply --type='method_call' --dest=org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager.PowerOff
> ```

This immediately invokes final shutdown binary without attempting to
stop any unit. So systemd starts killing spree with everything running.
This is actually documented on the page you mention.

> while this works ok:
> ```
> dbus-send --system --print-reply --type='method_call' --dest=org.freedesktop.login1 /org/freedesktop/login1 org.freedesktop.login1.Manager.PowerOff boolean:false
> ```
> 
> [1] https://www.freedesktop.org/software/systemd/man/org.freedesktop.systemd1.html#Methods
> [2] https://www.freedesktop.org/software/systemd/man/org.freedesktop.login1.html#Methods
> 
> Posting this here as it might be of interest to someone on the list.
> 
> Best regards,
> Manuel