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

[Daniel Walsh]

On 3/2/22 11:50, Lennart Poettering wrote:
> On Mi, 02.03.22 12:29, Manuel Wagesreither (ManWag at FastMail.FM) wrote:
>
>> Hi all,
>>
>> My embedded system is shutting down rather slow, and I'd like to find out the responsible processes.
>>
>> [ 7668.571133] systemd-shutdown[1]: Waiting for process: dockerd, python3
>> [ 7674.670684] systemd-shutdown[1]: Sending SIGKILL to remaining processes...
>>
>> Is there a way for systemd-shutdown to give me the PID of the
>> processes it waits for?
> The messages above are from the second phase of shutdown, the "killing
> spree phase": it kills processes/unmounts file systems/detaches
> storage/… that is left over from the first phase of shutdown. If stuff
> is terminated here, and in particular processes are killed this almost
> certainly indicates something is seriously broken in the first phase
> of shutdown. Or in other words: don#t try to debug the second phase
> too much, the first phase is where the brokeness is.
>
> Since this is dockerized stuff: look at docker, they are pretty bad at
> cooperating with systemd in the cgroup hierarchy, and they really need
> to clean up their own stuff properly when going down. If they don't do
> that, you need to fix that in Docker. Or in other words: talk to the
> docker people aout all this.
>
> That said, we could certainly show both the comm field and the PID of
> the offending processes. I am prepping a patch for that.
>
> Lennart
>
> --
> Lennart Poettering, Berlin
>
You could always look at Podman and CRI-O, which should work better with 
Systemd, or at least be more responsive to issues like this.