[tor-bugs] #23816 [Core Tor/Tor]: Use exponential backoff with jitter and/or tune its parameters

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#23816: Use exponential backoff with jitter and/or tune its parameters
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 Reporter:  nickm            |          Owner:  nickm
     Type:  defect           |         Status:  needs_review
 Priority:  Medium           |      Milestone:  Tor: 0.3.2.x-final
Component:  Core Tor/Tor     |        Version:
 Severity:  Normal           |     Resolution:
 Keywords:  review-group-24  |  Actual Points:
Parent ID:                   |         Points:
 Reviewer:  catalyst         |        Sponsor:  SponsorV
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Comment (by catalyst):

 rough estimate of mean delays:
 * existing: d,,i,, = base * ((m+1)/2)^i^ [ m = 3 regular; m = 2 testnet ]
 * full jitter: d,,i,, = base * m^i^/2 [ m = 2 per AWS blog ]
 * decorrelated jitter: d,,i,, = base * (m/2)^i^ [ m = 3 per AWS blog ]

 It looks like going to decorrelated jitter will cause the mean delays to
 increase more slowly than they already are, which seems like a helpful
 thing.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23816#comment:9>
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