[tor-bugs] #28663 [Core Tor/sbws]: sbws stops accumulating, silently

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#28663: sbws stops accumulating, silently
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 Reporter:  stefani        |          Owner:  (none)
     Type:  defect         |         Status:  new
 Priority:  Medium         |      Milestone:  sbws: 1.0.x-final
Component:  Core Tor/sbws  |        Version:  sbws: 1.0.2
 Severity:  Major          |     Resolution:
 Keywords:                 |  Actual Points:
Parent ID:  #28639         |         Points:
 Reviewer:                 |        Sponsor:
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Comment (by juga):

 Replying to [comment:7 anadahz]:
 > This bug is triggered after ~8 hours of sbws uptime.

 8h is the time it would take to complete the first prioritization loop.
 This confirm more my theory that sbws might be getting stall in that
 point, maybe because of race conditions (#27996)
 5 days ago, I commented these lines in longclaw's sbws and it's not
 stalling anymore:
 1. where it returns only a subset of the relays [0] and instead return all
 (the loop will take around 1 day, but measure all the relays that in the
 network found in the prioritization loop, not around 300).
 2. i commented the condition where sbws gives more priority to the relays
 that fails [1]. This is probably not the reason, but made sbws faster
 because it seems there're unstable relays that would get prioritized to be
 measured, but would fail again.

 I'd uncomment 1 by 1 those lines and see if it stalls again.

 There could be still other reasons as the one in #28639.

 [0]
 https://github.com/torproject/sbws/blob/c2b85b3f81456779f5882addbf78713acf8d66c9/sbws/lib/relayprioritizer.py#L89
 [1]
 https://github.com/torproject/sbws/blob/c2b85b3f81456779f5882addbf78713acf8d66c9/sbws/lib/relayprioritizer.py#L66

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/28663#comment:9>
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