Re: [quicwg/base-drafts] Persistent Congestion Time Threshold (#2365)

ianswett <notifications@github.com> Wed, 30 January 2019 12:09 UTC

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Subject: Re: [quicwg/base-drafts] Persistent Congestion Time Threshold (#2365)
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ianswett commented on this pull request.



>  
      // Start a new congestion epoch if the last lost packet
      // is past the end of the previous recovery epoch.
-     CongestionEvent(largest_lost_packet.time_sent)
+     CongestionEvent(newest_lost_packet.time_sent)
+
+     // Collapse congestion window if persistent congestion
+     if (InPersistentCongestion(oldest_lost_packet.time_sent)):

I'm starting to think we should pass in congestion_period and make it oldest_lost_packet - newest_lost_packet.

I think using Now() may be incorrect.  What if one packet is lost and then a few ACKs are lost.  In this case, Now() is substantially larger than oldest_lost_packet, but in fact only one packet was lost.

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