[tahoe-dev] [tahoe-lafs] #1157: new downloader could still get block data from shares with UEB/hashchain corruption (was: new downloader should reuse shares with only partial corruption)

[tahoe-lafs]

#1157: new downloader could still get block data from shares with UEB/hashchain
corruption
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     Reporter:  warner         |       Owner:           
         Type:  enhancement    |      Status:  new      
     Priority:  minor          |   Milestone:  undecided
    Component:  code-encoding  |     Version:  1.8β     
   Resolution:                 |    Keywords:           
Launchpad Bug:                 |  
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Comment (by warner):

 actually, I was less conversative than I thought. We *do* use partially-
 corrupted shares, as long as the corruption is limited to block data. If
 there is corruption in the hash trees or UEB, and we notice it (because we
 tried to get those fields from a given share), then we will abandon that
 share for the life of the {{{FileNode}}} instance. If we don't notice the
 corruption (because we already had those fields from some earlier share),
 we'll keep using it.

 So the only improvement we might make is to not give up on UEB-corrupted
 shares in the hopes of getting useful block data from them later (even
 though we must get the UEB from some other share).

 Updating the description to match.

-- 
Ticket URL: <http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1157#comment:1>
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