[tor-bugs] #20440 [Metrics/metrics-lib]: endless wait in BlockingIteratorImpl

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#20440: endless wait in BlockingIteratorImpl
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 Reporter:  iwakeh               |          Owner:  iwakeh
     Type:  defect               |         Status:  needs_review
 Priority:  High                 |      Milestone:  metrics-lib 1.6.0
Component:  Metrics/metrics-lib  |        Version:
 Severity:  Normal               |     Resolution:
 Keywords:                       |  Actual Points:
Parent ID:                       |         Points:
 Reviewer:                       |        Sponsor:
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Comment (by iwakeh):

 Replying to [comment:13 karsten]:
 > The fix looks good to me, even unrelated to this particular error case.
 What if an application starts reading descriptors and decides at some
 point to stop processing descriptors, possibly because a database
 connection has broke or the disk has run full or whatever.  In such a case
 the application shouldn't be forced to request all descriptors from the
 iterator until it's empty.  And the application shouldn't be forced to
 System.exit() just to kill the library thread.  In a way, we're only using
 a thread to read and parse descriptors to speed up the process and not do
 all this when the application asks for another descriptor.
 >
 > I'm still curious though: how did you reproduce this bug?  Can I have
 the data you mention above that would reproduce it?  (Or maybe I already
 have it, but where?)  Thanks!

 The data is not public, but check your mail (Oct 24, 2016)

 I think, it might be a concurrency issue or at least that affects metrics-
 lib in addition.
 For this discussion see ticket #21365.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/20440#comment:14>
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