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Comment by Magniquick | Hacker News Reader

Systemd timers do this natively btw, no need to hardcode And imho are also friendlier.

Timers also let you logical-AND elements within one simple declaration. Combine that with a random delay, and you can easily define a trigger such as "the 2nd Saturday of the month, anytime between midnight and 6AM":

  OnCalendar=Sat *-*-08..14 00:00:00
  RandomizedDelaySec=360min

You can tell a timer whether to re-use that same randomly-selected time during subsequent runs (FixedRandomDelay), or to re-roll the time for every trigger. They can also persist their last-run history across reboots, and trigger if they missed their previous time-slot.

The improved logic vs. cron is one of the features which makes my life easier, and so I started using systemd more often. IMHO some of the newer additions aren't quite as solid; but the basic units have proven to be very handy. Another example: The 'path' unit, which can trigger whenever a defined file is updated.

https://wiki.archlinux.org/title/Systemd/Timers

BSD cron has supported jitter for decades. This is strictly a linux problem.

It's a human problem. Noone "expects" their own "minimal" checks to compound. And everyone (re)implements periodic checks in ever-more-inventive ways. BSD cron solves this ? Alright. Does prometheus use it to schedule its periodic polling ? Do OTel collectors use it to smear their backend metrics uploads ? Does your own code use cron jobs for its "periodic" heartbeating ?

If the answer to that is all-yes, then my compliments to you. Alas ... at least my experience says that's not how things are done.

But systemd bad :[

People slowly are getting used to it. (Less so with journalctl)

journalctl is good idea executed terribly. It's builtin data format is massively wasteful and not even good at searching for data you want (often need to go thru all the files anyway)

Journalctl with SQLite or a columnar embedded database would be amazing for sysadmins. Current format is entirely useless

More like people were forced to use systemd and gave up due to lack of choice, along with an entire generation not old enough to know SysVinit.

The "forced to use systemd" meme is a weird inversion. No one complained about being "forced" to use sysvinit when their was no choice, but when distros started to use systemd, which still allows to use sysvinit style services, that's suddenly framed as an infringement of free choice.

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