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Comment by avmich | Hacker News Reader

Can we talk - or assume, or understand - about "average frequencies" of requests and still use Hz as units?

As the OP discusses, the current state of the standard formally disallows it: the SI specifies that hertzes are only to be used for periodic phenomena, and becquerels only for radioactivity.

Sure. A reasonable model for incoming requests within a short window of time is as a "Poisson process", which means the expected number of incoming requests within any interval is proportional to the length of that interval.

The parameter of that distribution is the expected (aka average) rate. If the intervals are time intervals, then the proper units of the parameter are events/second

Hertz is fixed frequency. Say you poll x times in second with set intervals. It is not measurement of discreet events say packet arriving. Probably best just to leave hertz out unless it is something that is actually fixed rate. So just leave it unitless.

If you define frequency as the derivative of the phase with respect to time, then you also have an instantaneous frequency which (at least formally) also has Hz as unit - even though it does not necessarily describe some real periodicity.

To measure discrete events, I would prefer as unit "events per second" instead of Hz.

No because everyone expects Hz to be as explained in TFA.

It is much more useful as a unit if 4Hz is 250ms event.

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