[tor-bugs] #4086 [Analysis]: Compare performance of TokenBucketRefillInterval params in simulated network

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#4086: Compare performance of TokenBucketRefillInterval params in simulated
network
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 Reporter:  arma                     |          Owner:       
     Type:  task                     |         Status:  new  
 Priority:  normal                   |      Milestone:       
Component:  Analysis                 |        Version:       
 Keywords:  performance flowcontrol  |         Parent:  #4465
   Points:                           |   Actualpoints:       
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Comment(by arma):

 Replying to [comment:18 robgjansen]:
 > There are two issue here: total capacity and capacity distribution. I'm
 telling you that the shape of the distribution is important because it
 affects how clients select relays (and, in turn, load distribution). You
 are telling me that total capacity is important for somewhat obvious
 performance reasons.

 Ah ha. Yes, there are two issues here: first is how we sample relays from
 the total list to decide which relays your simulated network will use.
 Second is how big those relays should be.

 I think the "how big they should be" is clearly the descriptor numbers.

 But how to sample them is an interesting open problem. I could see a
 strong argument for sampling them based on the consensus weights.

 > So, we need a metric that captures both: what do you think about
 weighting each difference (of the y-values in the CDFs) by the bandwidth
 (the x-value in the CDFs) so that differences between high bandwidth nodes
 means more than between low bandwidth nodes (differences in the tail of
 the CDF mean more than elsewhere)?

 Hm. I have no good intuition about what outcome that would give us. Is it
 aiming to be something in between the descriptor values and the consensus
 values?

 > In the meantime, I think it makes sense to run a set of experiments
 where relay capacity is based on observed bandwidth rather than consensus
 weights.

 I agree. It will at least remove some confusing variables.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4086#comment:19>
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