Found this as well which has more information about how systemd might shut down your user slice
https://serverfault.com/questions/1137788/how-to-debug-systemd-shutdown-failing-to-gracefully-shutdown which lnks to https://www.freedesktop.org/software/systemd/man/latest/systemd.kill.html#KillMode= if you've verified your process gets a KILL signal and no TERM before hand, and the various unit / sessions settings are configured to send TERM before KILL, I guess that would be a systemd bug. but I guess, more likely than a bug, would be that the (potentially complicated) interaction between how systemd manages processes and how it can be configured is not configured to send a TERM first. since there doesn't seem to be a way to turn on debugging so systemd tells you what it's doing, you may have to either code up a patch to add more logging to systemd, or manually check the (again, potentially complicated) settings to see how those settings are telling systemd to kill your user session / slice. that of course also requires understanding what a session or slice even is, which I don't claim to know. not trying to be unhelpful here -- I was looking into this cuz I wanted to learn more about systemd, and the answer seems to be "it's potentially quite complicated" On Fri, Mar 20, 2026 at 9:07 AM Daniel Sterling <[email protected]> wrote: > > from https://github.com/systemd/systemd/blob/main/src/shutdown/shutdown.c > > it looks like systemd does indeed try to term then kill all processes > > log_info("Sending SIGTERM to remaining processes..."); > broadcast_signal(SIGTERM, true, true, arg_timeout); > > log_info("Sending SIGKILL to remaining processes..."); > broadcast_signal(SIGKILL, true, false, arg_timeout); > > do you see those entries in your logs? > > On Fri, Mar 20, 2026 at 8:33 AM alain williams <[email protected]> wrote: > > > > I find that when I do a reboot or poweroff (from command line) running > > processes are not being sent SIGTERM. The one that really annoys me is a > > text > > editor not receiving it and thus me losing work. > > > > The systemd documentation says that it should be sent; good old init used > > to do > > this. > > > > Is the documentation wrong or do I need to tweak some config somewhere ? > > > > I am running Debian 13 with the mate desktop. MATE Terminal provides the > > terminal emulation. The editor is my own version of microemacs (which does > > handle SIGTERM correctly). > > > > The GUI (mate, etc) is actually irrelevant - the same thing happens to the > > editor being run on a console. > > > > TIA > > > > -- > > Alain Williams > > Linux/GNU Consultant - Mail systems, Web sites, Networking, Programmer, IT > > Lecturer. > > +44 (0) 787 668 0256 https://www.phcomp.co.uk/ > > Parliament Hill Computers. Registration Information: > > https://www.phcomp.co.uk/Contact.html > > #include <std_disclaimer.h> > >
