[tor-bugs] #14881 [Core Tor/Tor]: incorrect defaults when producing bandwidth-weights line in directory footer

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#14881: incorrect defaults when producing bandwidth-weights line in directory
footer
-------------------------------------------------+-------------------------
 Reporter:  robgjansen                           |          Owner:  pastly
     Type:  defect                               |         Status:
                                                 |  needs_revision
 Priority:  Medium                               |      Milestone:  Tor:
                                                 |  0.2.9.x-final
Component:  Core Tor/Tor                         |        Version:  Tor:
                                                 |  0.2.7
 Severity:  Normal                               |     Resolution:
 Keywords:  027-triaged-1-in, 028-triaged,       |  Actual Points:
  pre028-patch, tor-sponsorU-orphan,             |
  TorCoreTeam-postponed-201604, review-group-8   |
Parent ID:                                       |         Points:  3
 Reviewer:  mikeperry                            |        Sponsor:
                                                 |  SponsorU-can
-------------------------------------------------+-------------------------
Changes (by teor):

 * status:  needs_review => needs_revision


Comment:

 Thanks for getting this into usable form! We're almost there.
 Branches are easier, but we'll take either.

 Major issues:
 * Consensus method number 23 is already MIN_METHOD_FOR_SHARED_RANDOM.
 Please rebase on Tor master, and use consensus method number 24 for
 MIN_METHOD_FOR_INIT_BW_WEIGHTS_ONE.

 Minor issues:
 * The spacing in the changes file does not match the spacing in other
 changes files. This would require a manual tweak when producing the
 changelog, let's fix it now.

 Comments:
 * This changes behaviour in all tor networks, which is correct, but
 riskier. It does introduce a small inaccuracy into the public network
 consensus weights, but only 1/10000 (BW_WEIGHT_SCALE/bwweightscale).
 * Test networks will execute networkstatus_compute_bw_weights_v10 "Case
 2b", rather than the "Consensus with empty bandwidth" error case. Have you
 verified which sub-case of 2b they execute? Does this execute without any
 errors? I can do this check with chutney if you'd like.
 * Similarly, have you verified that the case that's executed in the
 current tor network works? Does this execute without any errors? It might
 be worth writing unit tests for each case with the new defaults, if these
 unit tests don't exist already.
 * Have you verified that the code is compatible with a mixed-version
 network? Chutney has a "mixed" target for this, but you must sym/hard link
 your current version of tor to tor-stable somewhere in your path.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/14881#comment:37>
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