An article detailing five lesser-known features of systemd timers, such as single-instance execution, second-resolution timing, monotonic events, manual triggering, and automatic reporting on failing services.
- systemd Timers: Modern replacement for cron with more control, flexibility, and higher resolution.
- One Instance at a Time: Automatically prevents multiple timer instances from running simultaneously to avoid resource conflicts.
- Second-Resolution Timing: Enables one-second resolution (vs. cron's one-minute) by setting
AccuracySec=1in the timer file. - Monotonic Events: Triggers timers based on system events like boot-up (
OnBootSec) or clock changes (OnClockChange). - Manually Trigger Timed Tasks: Launch timers and services manually for testing (
sudo systemctl start name-of-your.timerorname-of-your.service). - Automatically Report on Failing Services: Use
OnFailuredirective in service files to send notifications upon failure, supporting multiple notification methods (e.g., email, Slack). - systemd-analyze Calendar: Normalizes dates and times for use in
OnCalendarstatements.
Learn how to use timer interrupts (timers and event handling) with the ESP32 and ESP8266 programmed with MicroPython. Timer interrupts allow you to schedule and execute specific tasks at regular intervals or after a designated time delay.
