[tor-bugs] #7009 [Tor]: Handle unstable relays better

[Tor Bug Tracker & Wiki]

#7009: Handle unstable relays better
---------------------------------+------------------------------------------
 Reporter:  arma                 |          Owner:                    
     Type:  project              |         Status:  new               
 Priority:  normal               |      Milestone:  Tor: 0.2.5.x-final
Component:  Tor                  |        Version:                    
 Keywords:  tor-relay, SponsorJ  |         Parent:                    
   Points:                       |   Actualpoints:                    
---------------------------------+------------------------------------------

Comment(by nickm):

 Comments:

   * This doesn't really have much to do with dynamic IPs.
   * There's a lot of space going to relays that clients mostly don't use.
 If we realizing that if we discarded all nodes with Bandwidth=X for X
 under 100 we'd dump 48% of the nodes in the md consensus, but only about
 half of a percent of the total capacity according to Bandwidth=X.
       * If we decide to do that, though, we should re-run the
 measurements.
   * bzip2 is a clear win.
   * For diffs, the "diff -e" output is (as predicted) a clear winner,
 followed by a kludgey roll-our-own format.
       * The main reason why diff -e wins is that my roll-my-own test
 kludge format doesn't handle headers and footers so nicely.  In quick-and-
 dirty tests: if it were considering only the body, it would be within 3%
 of diff -e.
   * There still isn't a good C library we can link for diff.  Otherwise,
 we could do worse than exec as needed and require a working diff on every
 Tor directory, I suppose.
   * If we don't need so much bandwidth weight granularity, we could win
 some space by dropping it.
   * Rounding bandwidths off helps a little, but I'm not sure what we lose
 by doing so.
   * We don't actually know what fraction of clients download a new
 consensus with what period.  Sure, if you're online constantly, you get a
 new one every 2-4 hours... but is that typical?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7009#comment:10>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online