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

Nick Banks <notifications@github.com> Thu, 07 February 2019 19:29 UTC

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

Hmm, well then we'd have to make two changes to achieve that behavior.
1. Use `newest_lost_packet - oldest_lost_packet` for the time window.
2. Make the threshold 2 PTO instead of 3.

Without the second part above, an ACK of pkt 4 would produce a loss window of only 3 seconds (3 - 0), right?

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