#7195 BLOC Never A: Corrupted multiple downloads at the same time

[Zarro Boogs per Child]

#7195: Corrupted multiple downloads at the same time
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  Reporter:  cjb        |       Owner:  erikos        
      Type:  defect     |      Status:  new           
  Priority:  blocker    |   Milestone:  Never Assigned
 Component:  datastore  |     Version:  Update.1      
Resolution:             |    Keywords:                
  Verified:  0          |    Blocking:                
 Blockedby:             |  
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Changes (by mstone):

  * owner:  tomeu => erikos


Comment:

 After reviewing the Browse source code, I think I see two problems in
 downloadmanager.py:

 1. According to the log, we're creating two DownloadManagers. Why on earth
 are we creating two DownloadManagers?

 2. Empirically, we're seeing interleaved writes. However, all data
 transfer is done by xulrunner; we just supply it a target path.
 Consequently, I infer that we're creating two Downloads (Transfers) to the
 same path. We should never ever have two transfers to the same target path
 if that target path is a local file.

 Next question: did I miss something? Is there some reason why the two
 DownloadManagers we create are going to return distinct file paths?

 Final question: what should we do? My preference at the moment is to use a
 synchronization mechanism (e.g. a lock) to deduplicate Transfer target
 paths. Comments?

-- 
Ticket URL: <http://dev.laptop.org/ticket/7195#comment:1>
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