[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 robgjansen):

 Replying to [comment:13 arma]:


 > Replying to [comment:6 robgjansen]:
 >
 > > '''Bulk performance''': Time to first byte improves when scheduling
 with EWMA, but does not improve when scheduling with RR. This is mostly
 because RR is outperforming EWMA quite significantly to begin with.
 Similarly, time to last byte only improves when scheduling with EWMA, but
 actually hurts performance when scheduling with RR. Again, RR appears to
 beat out EWMA for bulk clients.
 > >
 >
 > Rob: how do you say that "RR appears to beat out EWMA for bulk clients"
 when slide 4 of refill-perf-ewma0 shows that refilling once per second is
 best, and slide 4 of refill-perf-ewma30 shows that refilling once per
 second is worst? It seems your graphs show that if we're going to refill
 more than once a second then the bulk clients are better off with EWMA.

 I was looking at the overall performance regardless of the refill
 interval. My point was that if you e.g. combine all 4 lines into one on
 each of ewma0 and ewma30, RR would beat EWMA (although only slightly).

 In the context of what you care about, which appears to be refilling more
 than once per second, then I agree that EWMA improves the situation for
 bulk clients (based on this set of graphs, that is). In this case you
 essentially want to ignore the solid black line on each graph, which means
 you are removing the worst case from EWMA and the best from RR. My
 "combine lines" approach would then only include the colored lines, and
 EWMA then looks better.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4086#comment:16>
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