[systemd-devel] confusing output with a swap device missing

[Zbigniew Jędrzejewski-Szmek]

Hi,

I booted a system after (inadvertently) changing the UUID of a swap
device. This causes the .swap unit to time-out, and since swap.target
wants the .swap unit, this makes the whole boot very slow.

Unfortunately, understanding what is the cause of the timeout is not
trivial, unless one knows what to look for.

$ journalctl -a |grep Startup
May 23 15:44:31 fedora-15 systemd[1]: Startup finished in 740ms 270us (kernel) + 1s 934ms 75us (initrd) + 1min 33s 387ms 780us (userspace) = 1min 36s 62ms 125us.

$  systemd-analyze blame
  2746ms network.service
   355ms udev-settle.service
...

(nothing here)

$  systemctl status swap.target 
swap.target - Swap
	  Loaded: loaded (/usr/lib/systemd/system/swap.target; static)
	  Active: active since Wed, 23 May 2012 15:44:28 +0200; 34min ago

(Completely misleading -- no swap devices were activated...)

$  systemctl --failed
...
(nothing interesting here)

$ systemctl --failed --all
...
(nothing interesting here)

$ systemd-analyze plot
Here one can see that swap.target is the first thing which is active a long delay.

$ systemctl show swap.target
...
Wants=dev-disk-by\x2duuid-xxxxxx.swap

$ systemctl status dev-disk-by\x2duuid-xxxxxx.swap
...
Active: inactive (dead)

(OK, now it becomes obvious... but such information should be more visible.)

$ journalctl
...
May 23 15:42:59 fedora-15 systemd-tmpfile[519]: Successfully loaded SELinux database in 21ms 628us, size on heap is 536K.
May 23 15:44:28 fedora-15 systemd[1]: Job dev-disk-by\x2duuid-xxxxxx.device/start timed out.
May 23 15:44:28 fedora-15 systemd[1]: Job dev-disk-by\x2duuid-xxxxxx.swap/start failed with result 'dependency'.
May 23 15:44:28 fedora-15 systemd[1]: Job dev-disk-by\x2duuid-xxxxxx.device/start failed with result 'timeout'.

It would be really nice if this information which is buried in the logs
could be displayed more prominently when one uses other diagnostic tools.

Zbyszek