6d510012b7
When we moved the time to 1 minute after the timer would've elapsed, systemd could pick RandomizedDelaySec= <= 1 minute which would then cause the timer to elapse immediately and the InactiveExitTimestamp= to get recalculated including a new next elapse time that would be for the next "window": systemd[1]: timer-RandomizedDelaySec-30785.timer: Adding 3.634672s random time. systemd[1]: timer-RandomizedDelaySec-30785.timer: Realtime timer elapses at Fri 2025-11-07 00:10:03 UTC. systemd[1]: timer-RandomizedDelaySec-30785.timer: Timer elapsed. systemd[1]: timer-RandomizedDelaySec-30785.timer: Changed waiting -> running systemd[1]: Found unit timer-RandomizedDelaySec-30785.timer at /run/systemd/system/timer-RandomizedDelaySec-30785.timer (regular file) systemd[1]: Preset files say disable timer-RandomizedDelaySec-30785.timer. systemd[1]: timer-RandomizedDelaySec-30785.timer: Got notified about unit deactivation. systemd[1]: timer-RandomizedDelaySec-30785.timer: Adding 8h 39min 26.166418s random time. systemd[1]: timer-RandomizedDelaySec-30785.timer: Realtime timer elapses at Sat 2025-11-08 08:49:26 UTC. systemd[1]: timer-RandomizedDelaySec-30785.timer: Changed running -> waiting ... TEST-53-TIMER.sh[1008]: InactiveExitTimestamp=Thu 2025-11-06 23:00:00 UTC TEST-53-TIMER.sh[1010]: ++ systemctl show -P NextElapseUSecRealtime timer-RandomizedDelaySec-30785.timer TEST-53-TIMER.sh[905]: + NEXT_ELAPSE_REALTIME='Sat 2025-11-08 08:49:26 UTC' TEST-53-TIMER.sh[1011]: ++ date '--date=Sat 2025-11-08 08:49:26 UTC' +%s TEST-53-TIMER.sh[905]: + NEXT_ELAPSE_REALTIME_S=1762591766 TEST-53-TIMER.sh[905]: + : 'Next elapse timestamp should be Fri 2025-11-07 00:10:00 UTC <= Sat 2025-11-08 08:49:26 UTC <= Fri 2025-11-07 22:10:00 UTC' TEST-53-TIMER.sh[905]: + assert_ge 1762591766 1762474200 TEST-53-TIMER.sh[1012]: + set +ex TEST-53-TIMER.sh[905]: + assert_le 1762591766 1762553400 TEST-53-TIMER.sh[1013]: + set +ex TEST-53-TIMER.sh[1013]: FAIL: '1762591766' > '1762553400' Technically, the race is still there, but the window for it should be _much_ smaller now (< 1s on a reasonably fast system). Let's hope that's enough. Resolves: #39594
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