[tor-bugs] #20534 [Core Tor/Tor]: Revise hard-coded download schedules

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#20534: Revise hard-coded download schedules
-------------------------------------------+-------------------------------
 Reporter:  teor                           |          Owner:  nickm
     Type:  defect                         |         Status:  accepted
 Priority:  Medium                         |      Milestone:  Tor:
                                           |  0.3.0.x-final
Component:  Core Tor/Tor                   |        Version:  Tor:
                                           |  0.2.9.1-alpha
 Severity:  Normal                         |     Resolution:
 Keywords:  regression, CoreTorTeam201611  |  Actual Points:
Parent ID:  #20499                         |         Points:  0.5
 Reviewer:                                 |        Sponsor:
-------------------------------------------+-------------------------------

Comment (by teor):

 Turns out that sometimes I just can't do my sums right.
 Here are the actual figures for each case with exponent 4 (multiplier 3):

 Initial delay 0: (most schedules)
 {{{
 Attempt / Failure       Min Increment   Max Increment   Average Minimum
 Maximum
 1       0       0       0       0       0
 2       1       2       2       1       2
 3       1       8       5       2       10
 4       1       32      13      3       42
 5       1       128     33      4       170
 6       1       512     84      5       682
 7       1       2048    211     6       2730
 }}}

 Initial delay 6: (client bootstrap from authorities)
 {{{
 Attempt / Failure       Min Increment   Max Increment   Average Minimum
 Maximum
 1       0       0       6       6       6
 2       1       20      11      7       26
 3       1       80      27      8       106
 4       1       320     69      9       426
 5       1       1280    174     10      1706
 }}}

 Initial delay 1200: (bridge client bridge descriptors)
 {{{
 Attempt / Failure       Min Increment   Max Increment   Average Minimum
 Maximum
 1       0       0       1200    1200    1200
 2       1       3602    1802    1201    4802
 3       1       14408   4505    1202    19210
 4       1       57632   11263   1203    76842
 }}}

 And for test networks, with exponent 3 (multiplier 2):
 Initial delay 0: (most schedules)
 {{{
 Attempt / Failure       Min Increment   Max Increment   Average Minimum
 Maximum
 1       0       0       0       0       0
 2       1       2       2       1       2
 3       1       6       4       2       8
 4       1       18      9       3       26
 5       1       54      19      4       80
 6       1       162     39      5       242
 7       1       486     79      6       728
 }}}

 Initial delay 20 (bridge client bridge descriptors):
 {{{
 Attempt / Failure       Min Increment   Max Increment   Average Minimum
 Maximum
 1       0       0       20      20      20
 2       1       42      42      21      62
 3       1       126     84      22      188
 }}}

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/20534#comment:19>
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