[tahoe-lafs-trac-stream] [tahoe-lafs] #1543: rearrange share format to make downloads faster

[tahoe-lafs]

#1543: rearrange share format to make downloads faster
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     Reporter:  warner         |      Owner:
         Type:  enhancement    |     Status:  new
     Priority:  major          |  Milestone:  undecided
    Component:  code-encoding  |    Version:  1.9.0a1
   Resolution:                 |   Keywords:  performance
Launchpad Bug:                 |
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Comment (by zooko):

 Replying to [comment:3 zooko]:
 > We could write out the 32 leafs, followed by the 12 uncles, followed by
 space sufficient for 52 more uncles (in case the file grows). Each of
 these 64-hashvalue-wide records would take a total of 2048 bytes, and a
 typical reader would need to slurp only (part of) one or two of these
 records in order to validate up to 32 or 64 blocks of data, which would be
 around 1.3 or 2.6 MiB.

 Anybody who followed this idea closely may have noticed a minor error here
 -- the records would be 96 hashvalues wide, not 64, so to download an
 entire record would take 3072 bytes, not 2048 bytes.

-- 
Ticket URL: <http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1543#comment:4>
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