[tor-bugs] #25687 [Core Tor/Tor]: over-report of observed / self-measure bandwidth on fast hardware -- important to torflow / peerflow (was: extreme over-report of observed / self-measure bandwidth on fast hardware -- critical to torflow / peerflow)

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#25687: over-report of observed / self-measure bandwidth  on fast hardware --
important to torflow / peerflow
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 Reporter:  starlight     |          Owner:  (none)
     Type:  defect        |         Status:  new
 Priority:  Medium        |      Milestone:  Tor: unspecified
Component:  Core Tor/Tor  |        Version:  Tor: 0.3.3.3-alpha
 Severity:  Normal        |     Resolution:
 Keywords:                |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Comment (by starlight):

 Realized the +60% number I threw down is flawed and went back over data
 and configurations carefully.  Nonetheless the problem is, or was
 significant.

 Found an example where, with a tc-police rate limit, reported self-measure
 was 19% in excess of the limit.  Daemon version 0.2.6.10.  At the time of
 the observation the relay was overrated in the consensus 50% and flooded
 with ingress data at about 150% of the cap.  More typically have seen
 continuous overrating at +5% with tc and a reasonable consensus weight.

 I retract the assertion that KIST increased the problem--admit that I do
 not know.

 Also stand by the recommendation that self-measure should not include
 peaks resulting from adaptive ISP rate limits and am sure that I've seen
 this.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/25687#comment:4>
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