[tor-bugs] #28305 [Metrics/Statistics]: Include client numbers even if we think we got reports from more than 100% of all relays

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#28305: Include client numbers even if we think we got reports from more than 100%
of all relays
--------------------------------+------------------------------
 Reporter:  karsten             |          Owner:  metrics-team
     Type:  defect              |         Status:  new
 Priority:  High                |      Milestone:
Component:  Metrics/Statistics  |        Version:
 Severity:  Normal              |     Resolution:
 Keywords:                      |  Actual Points:
Parent ID:                      |         Points:
 Reviewer:                      |        Sponsor:
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Comment (by teor):

 I wonder if it's more than a rounding error.

 How is frac calculated?

 I wonder if you're choosing a point in time to calculate the consensus
 weight fraction.

 What happens if relays that submit statistics are offline at that point in
 time?
 But it submits statistics later, when it comes back online?

 If that relay has a weight N, and 100% of relays submit, then your frac
 calculation will be:

    100     the relays that submitted statistics
 ---------
 (100 - N)  the relays that were online at the point in time you chose

 When it should be:

 100 the relays that submitted statistics
 ---
 100 all the relays that could have submitted statistics

 I can't find the codebase or the metrics statistics explanation to check.
 (I tried searching for the code online. And I tried the metrics wiki
 pages.)

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/28305#comment:1>
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