[tor-bugs] #6538 [Tor Client]: Use bit-twiddling tricks to make choose-by-bandwith algorithm even more time-invariant

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#6538: Use bit-twiddling tricks to make choose-by-bandwith algorithm even more
time-invariant
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 Reporter:  nickm        |          Owner:                    
     Type:  enhancement  |         Status:  needs_review      
 Priority:  normal       |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Client   |        Version:                    
 Keywords:               |         Parent:                    
   Points:               |   Actualpoints:                    
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Comment(by rransom):

 Replying to [comment:14 nickm]:
 > wrt the scale issue, I'm seeing typical values that suggest that the
 integer roundoff doesn't matter much here.  Is their counterveiling
 evidence?

 Whether integer roundoff matters or not depends on the current value of
 `weight_scale`.


 Also, are you sure that the C comparison operator you want to leave in
 (`tmp > rand_bw`) will be implemented in constant time on 32-bit systems?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/6538#comment:15>
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