[tahoe-dev] [tahoe-lafs] #1180: put more DYHBs into flight at once when K is larger

[tahoe-lafs]

#1180: put more DYHBs into flight at once when K is larger
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 Reporter:  zooko                                           |           Owner:      
     Type:  defect                                          |          Status:  new 
 Priority:  major                                           |       Milestone:  soon
Component:  code-network                                    |         Version:  1.8β
 Keywords:  easy immutable download performance regression  |   Launchpad Bug:      
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 As mentioned in comment:8:ticket:448, the new downloader code in v1.8.0
 will put at most 10 DYHBs into flight at once. This is perfect when
 {{{K=3}}}, but as {{{K}}} gets larger it is increasingly likely that the
 hardcoded limit of {{{10}}} will induce delay at the beginning of a
 download or cause the downloader to overlook a better-performing server.
 As Brian suggested on #448, a better limit would be something like {{{K *
 3}}}.

 (Note: everyone that I know of uses the default settings of {{{K=3,
 M=10}}}. The theoretical maximum value of {{{K}}} is 256. I think there
 might be other problems with using {{{K}}} greater than about {{{100}}},
 such as a worse rate of a storage server failing during your download, but
 I'm not sure.)

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Ticket URL: <http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1180>
tahoe-lafs <http://tahoe-lafs.org>
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