Comment # 1 on bug 1156421 from Fabian Vogt

Created attachment 823824 [details]
journalctl

What's in /var/log/journal and /run/log/journal?

I think I can reproduce this here. The issue appears to be that
systemd-journal-flush.service runs, but does somehow not cause a flush.

Snippet from the journal during bootup:

Oct 31 07:32:11 localhost systemd[1]: Starting Flush Journal to Persistent
Storage...
Oct 31 07:32:11 localhost systemd-journald[521]: Runtime Journal
(/run/log/journal/88c7cea6795b4428909767e3e81c15bd) is 5.9M, max 47.2M, 41.3M
free.
Oct 31 07:32:11 localhost kernel: audit: type=1400 audit(1572507131.859:6):
apparmor="STATUS" operation="profile_load" profile="unconfined" name="klogd"
pid=584 comm="apparmor_parser"
Oct 31 07:32:11 localhost systemd[1]: Started Flush Journal to Persistent
Storage.

That apparently didn't work, it still writing to /run/log/journal.

Snipped from the journal after restarting systemd-journal-flush.service
manually:

Oct 31 07:44:53 localhost systemd[1]: Starting Flush Journal to Persistent
Storage...
Oct 31 07:44:53 localhost systemd-journald[521]: Time spent on flushing to /var
is 108.202ms for 876 entries.
Oct 31 07:44:53 localhost systemd-journald[521]: System Journal
(/var/log/journal/88c7cea6795b4428909767e3e81c15bd) is 24.0M, max 1.4G, 1.4G
free.
Oct 31 07:44:53 localhost tallow[960]: Journal was rotated, resetting
Oct 31 07:44:53 localhost systemd[1]: Started Flush Journal to Persistent
Storage.

Here it switched to /var successfully. So the question is why it does not
happen (reliably?) when running during boot?