[tor-bugs] #5235 [Tor Directory Authority]: 550 Hz warn-level log spam on dirauth (“[warn] Weighted bandwidth is 0.000000...”)

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#5235: 550 Hz warn-level log spam on dirauth (“[warn] Weighted bandwidth is
0.000000...”)
-------------------------------------+--------------------------------------
 Reporter:  ln5                      |          Owner:                    
     Type:  defect                   |         Status:  needs_review      
 Priority:  normal                   |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Directory Authority  |        Version:                    
 Keywords:  easy                     |         Parent:                    
   Points:                           |   Actualpoints:                    
-------------------------------------+--------------------------------------
Changes (by andrea):

  * status:  new => needs_review


Comment:

 This patch rate-limits the message; since this function is called very
 frequently, it would probably be advisable to apply similar rate-limiting
 to the other two warning messages it can emit ("Round-off error in
 computing bandwidth had an effect on which router we chose", "Consensus is
 not listing bandwidths. Defaulting back to old router selection
 algorithm.").

 For possible further investigation: why would this sum to zero?  The
 function exits early if the list is empty, so this message can only be
 emitted if the list contains one or more nodes which contribute zero
 bandwidth to the total and none that contribute non-zero bandwidth.  A
 node can contribute zero bandwidth if node->rs->bandwidth is zero, or if
 all the weight factors applied are zero.  Which is it that has occurred
 here?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/5235#comment:3>
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