[tahoe-dev] [tahoe-lafs] #778: "shares of happiness" is the wrong measure; "servers of happiness" is better

[tahoe-lafs]

#778: "shares of happiness" is the wrong measure; "servers of happiness" is
better
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 Reporter:  zooko               |           Owner:  kevan
     Type:  defect              |          Status:  new  
 Priority:  critical            |       Milestone:  1.6.0
Component:  code-peerselection  |         Version:  1.4.1
 Keywords:  reliability         |   Launchpad_bug:       
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Comment(by zooko):

 Okay I read your explanation and followed along using the links that you
 embedded and I think you are right.  I hope you write that unit test or
 two when you get back from class!

 To fix this in terms of shares-of-happiness I guess
 [source:src/allmydata/immutable/upload.py?rev=20090815112846-66853-7015fcf1322720ece28def7b8f2e4955b4689862#L753
 CHKUploader.set_shareholders()] could also give an integer "already
 uploaded shares" to the encoder and the encoder could add that integer to
 the {{{len(self.landlords)}}} that is uses to decide if there is still a
 chance of success.

 To fix it in terms of servers-of-happiness, I suspect that
 {{{CHKUploader.set_shareholders()}}} would need to pass more information
 to the encoder, perhaps telling the encoder everything it knows about
 which servers already have which shares.  I'm not entirely sure how your
 current patch works, but I'll write more about that in a separate comment.

-- 
Ticket URL: <http://allmydata.org/trac/tahoe/ticket/778#comment:67>
tahoe-lafs <http://allmydata.org>
secure decentralized file storage grid