[tor-bugs] #4682 [Tor Relay]: Evaluate proposal 182 and compare it to other designs

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#4682: Evaluate proposal 182 and compare it to other designs
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 Reporter:  karsten    |          Owner:                           
     Type:  project    |         Status:  new                      
 Priority:  normal     |      Milestone:  Sponsor F: March 15, 2012
Component:  Tor Relay  |        Version:                           
 Keywords:             |         Parent:                           
   Points:             |   Actualpoints:                           
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Comment(by Flo):

 Karsten asked me to post the comments we discussed via email here too:

  * We tested the patch (cf. #4712) for several weeks on our relays. In
 case of non exit and non directory mirrors the results are great: >90% of
 all cells get forwarded immediately without any measurable latency.
 According to our measurements this value is at about 70% otherwise only.

  * In case of directory mirrors the results depend on the configured
 bandwidth, the new introduced parameter "OutgoingBandwidthBurst" (cf. M in
 proposal 182) and the amount of directory traffic seen at the relay.
 Overall, we can say it gets better too but there exist some open
 questions: What is the relationship between OutgoingBandwidthBurst and the
 configured rate limiting (magic number vs. ratio)? In the end, is
 OutgoingBandwidthBurst and BandwidthBurst the same?

  * Due to doubts on illegal issues with exit relays our university does
 not allow us to run them. Thus we could not test the patch in this
 environment yet.

  * Currently our implementation does not work with bufferevents. For me
 this seems a bit tricky to implement. In this case we still need to do
 some work.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4682#comment:3>
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