The restart-trigger subtest occasionally fails on CI with:
+ assert_eq 0 1
FAIL: expected: '1' actual: '0'
even though the timer fires correctly and the echo message is in fact
written to the journal. The failure happens because the test relies on
`journalctl --unit=$UNIT_NAME` to find the message, and that filter is
based on the cgroup journald looks up for the writer PID at the time
the stdout message is received.
For very short-lived processes spawned via systemd-executor (like
`echo`), that lookup is racy: the writer's `/proc/$PID/cgroup` can
still resolve to `/init.scope` (systemd-executor's own cgroup) rather
than the service's cgroup, so the message ends up attributed to
`init.scope` and `--unit=` filtering misses it.
__CURSOR=s=6f90ff5b6a0e47c3a527a9b4892af965;i=f8ed;b=3dad0cc689a04781879e4dd846d24432;m=17703dc;t=6513be1be2506;x=8d3009a687724b5e
__REALTIME_TIMESTAMP=1778167492519174
__MONOTONIC_TIMESTAMP=24576988
__SEQNUM=63725
__SEQNUM_ID=6f90ff5b6a0e47c3a527a9b4892af965
_BOOT_ID=3dad0cc689a04781879e4dd846d24432
_HOSTNAME=H
PRIORITY=6
SYSLOG_FACILITY=3
_UID=0
_GID=0
_CAP_EFFECTIVE=1ffffffffff
_SYSTEMD_CGROUP=/init.scope
_SYSTEMD_UNIT=init.scope
_SYSTEMD_SLICE=-.slice
_EXE=/usr/lib/systemd/systemd-executor
_TRANSPORT=stdout
_COMM=18
_MACHINE_ID=89ef83adc0bc4a33a83a227201b57203
_RUNTIME_SCOPE=system
_PID=816
_CMDLINE=/usr/lib/systemd/systemd-executor --deserialize 50 --log-level debug,console:info --log-target journal-or-kmsg
_STREAM_ID=8e8e4166c99e40afaa58bcd04a50a7f4
SYSLOG_IDENTIFIER=echo
MESSAGE=Hello from timer 29581
Note _SYSTEMD_UNIT=init.scope / _SYSTEMD_CGROUP=/init.scope on the
echo output: this is what causes `--unit=timer-restart-14362` to
return 0 hits. The test failure logs from the same run confirm this:
+ JOURNAL_TS=1778160292
+ journalctl -p info --since=@1778160292 --unit=timer-restart-14362 '--grep=Hello from timer 29581'
-- No entries --
+ systemctl restart timer-restart-14362.timer
...
+ date '--set=+2 hours'
Thu May 7 15:24:52 UTC 2026
+ sleep 1
...
echo[816]: Hello from timer 29581
...
++ journalctl -q -p info --since=@1778160292 --unit=timer-restart-14362 '--grep=Hello from timer 29581'
++ wc -l
+ assert_eq 0 1
FAIL: expected: '1' actual: '0'
For comparison, in a passing local run the same message is attributed
correctly to the service unit (_SYSTEMD_UNIT=timer-restart-24147.service),
so `--unit=` matches.
Work around the underlying journald race in the test by setting an
explicit `SyslogIdentifier=` on the service and matching with `-t` plus
the unique grep pattern: `SyslogIdentifier` is carried over the stdout
stream protocol and is not affected by the cgroup lookup race.
Co-developed-by: Claude Opus 4.7 <noreply@anthropic.com>
System and Service Manager
Details
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Information about build requirements is provided in the README file.
Consult our NEWS file for information about what's new in the most recent systemd versions.
Please see the Code Map for information about this repository's layout and content.
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