[tor-bugs] #5608 [Metrics Data Processor]: Order of sanitizing bridge descriptor tarballs matters even though it shouldn't

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#5608: Order of sanitizing bridge descriptor tarballs matters even though it
shouldn't
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 Reporter:  karsten                 |          Owner:  karsten
     Type:  defect                  |         Status:  new    
 Priority:  normal                  |      Milestone:         
Component:  Metrics Data Processor  |        Version:         
 Keywords:                          |         Parent:         
   Points:                          |   Actualpoints:         
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 There's a bug in how metrics-db tries to repair references between bridge
 network statuses, server descriptors, and extra-info descriptors.  In
 theory, the order of processed tarballs shouldn't matter, because we have
 a mapping file with hashed bridge fingerprint, descriptor publication
 time, server descriptor digest, and extra-info digest.  But apparently
 this approach is buggy.  I just tried sanitizing 1 week of tarballs in
 forward and in reverse order.  The result was that sanitized descriptors
 differed.  I suspect the problem is that bridges can publish more than 1
 descriptor in a single second, but I'm not sure yet.  I'm also not sure
 whether this leads to data loss or not.  More analysis required.  We might
 have to sanitize all bridge descriptors again.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/5608>
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