Slow shutdown with systemd >= 247

[flaphoschi]

systemd version the issue has been seen with

247

Used distribution

Archlinux
Using GNOME and NetworkManager without wait-online and dispatcher. For WiFi encryption iwd is in use instead of wpa_supplicant. To increase random number generation either rngd-tools or haveged.

Linux kernel version used (uname -a)

Linux cupcake 5.9.11-arch2-1 #1 SMP PREEMPT Sat, 28 Nov 2020 02:07:22 +0000 x86_64 GNU/Linux

CPU architecture issue was seen on

x86_64 (Intel SandyBridg i7-2640M CPU)

Expected behaviour you didn't see

Computer should shutdown quickly i.e. less than five seconds.

Unexpected behaviour you saw

Not 100% reproduceable, about in one of five shutdowns or reboots user@1000.service seems to timeout during shutdown after 120 seconds.

Steps to reproduce the problem

1.) boot computer
2.) login into graphic environment // seems to make the issue much more likely
3.) systemctl reboot
4.) if (reboot_is_quick) { jump to 1; } // should be slow in one of five
5.) be patient 🙂

If the shutdown is slow you will probably see only a blinking cursor. I've managed to see sometimes the message systemd-shutdown[1]: Waiting for process: dbus-daemon, systemd, rngd, gpg-agent when I press Ctrl+Alt+Del, Esc, Ctrl+c or shortly the power button. I've seen here various processes, systemd is obviously always included.

slow_shutdown_cutout.txt
Please see line 514 - 515.

Thank you
Stay confident!

[andreaskem]

Sounds similar to this bug, supposedly fixed by this commit.

[flaphoschi]

Thank you Andreas! That explains why I had no issues with pure TTY sessions. I've search everywhere for combinations of the words "systemd, hang, slow" but not "delay" 😋