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Comment by hyperman1 | Hacker News Reader

You see the same thing with e.g. cron jobs, where everyone schedules on xx:00 or xx:30. No communication needed, it's just natural. More senior people recognize this and add randomness to their start times or skew a bit.

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I always recommend to use weird numbers for different tasks. That way, you can see "oh my system is under severe load at *:13 (or 17, 23, 42, ...). That must be this cron job"

I do a similar thing with ping payload sizes to be able to fingerprint the traffic: I’ll use prime numbered packet sizes so that they can be detected even when the packet sizes are summed.

Btw, one of those numbers is not like the others (has more prime factors that evenly divide 60).

Good point. 7,11,13... do not repeat every hour.

It's often failing of the tools used, cron (and various other OS equivalents) just doesn't have good facilities to it.

Systemd timers have some, for example RandomizedOffsetSec=30m on 30m job will spread it nicely.

I'd also like if schedulers just had option "just fit it in with other jobs and fire it with this rough interval when there is least amount of other jobs running"

You ought to use RandomizedDelaySec=xxx

Depends. If you want a breadcrumb trail, use primes. If you want no noticeable effect at all, or cannot imagine a traffic bump that you'll want to decipher, use random offsets.

It’s entirely possible the battery controllers are running linux too

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