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by tuetuopay 53 days ago
Well the SI unit for request rate is … requests/s. Just like speed is m/s and not something bespoke.

However when the infra is crumbling under requests (one could say decaying), then becquerel seems appropriate

2 comments

For it to be an SI unit, shouldn't you be able to express it in terms of the 7 SI base units?
The requests would be a dimension-less quantity. There are a few examples of what those are and how they fit in:

- The frames in frames per second are dimensionless, thus the SI unit for FPS is frames/s. When the frames are periodic, such as monitor refresh rates are, the unit is Hz.

- Percentages are dimensionless quantities too, produced by divinding two quantities of the same dimension (ie unit). CPU%? That’s "busy second per second", which is dimensionless, and expressed as a percentage.

A dimensionless quantities don’t have any physical backing reality in terms of the, well, dimension in which you could measure it. Time, space, mass, etc.

Fun fact: angles are dimensionless! Both degrees and radians are just shorthands as divisions of the unit circle.

Think of those as event counts in an arrival process, then think of the events as impacts or strikes, and eventually you can come to the unit of countable Hurts.

These counts have implicit measurement windows since they are aperiodic. Rather than Hs representing "counts per second" akin to Hz being "cycles per second", I think we should combine it with an explicit window annotation. So 100 Hs/1s is the same rate as 6000 Hs/60s but with one second versus one minute counting interval.

You could also use the mol to count requests. It's somewhat inconveniently large, so 1 request/s turns into about 1.661ymol/s of requests.
And what if something goes from rest to light speed every second to average 1 m/s over the second. Is that the same thing as smooth 1 m/s?