[tor-bugs] #2506 [Tor Relay]: Design and implement a more compact GeoIP file format

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#2506: Design and implement a more compact GeoIP file format
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 Reporter:  rransom      |          Owner:  endian7000        
     Type:  enhancement  |         Status:  needs_review      
 Priority:  normal       |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Relay    |        Version:                    
 Keywords:               |         Parent:                    
   Points:               |   Actualpoints:                    
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Comment(by nickm):

 I did some quick tests on what to do if we ever need to handle over 256
 country codes.  Using a varint in the main data file to encode both run
 lengths and countries is less than 1% more expensive than using a single
 byte for countries, so I suggest that we future-proof here by using a
 varint for both.

 I also tried a variant where we only provide special short codes for run-
 lengths that appear N or more times, and encode the others literally as
 (total_num_codes+actual_value).  No value of N that I tried provided more
 than 4% savings, so it's probably not worth it.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2506#comment:14>
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