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Re: [quicwg/base-drafts] Persistent congestion pseudocode to match text (#4010)

Martin Thomson <notifications@github.com> Tue, 18 August 2020 04:40 UTC

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Date: Mon, 17 Aug 2020 21:40:21 -0700
From: Martin Thomson <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Persistent congestion pseudocode to match text (#4010)
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@martinthomson commented on this pull request.



>       pto = smoothed_rtt + max(4 * rttvar, kGranularity) +
        max_ack_delay
-     congestion_period = pto * kPersistentCongestionThreshold
+     pc_period = pto * kPersistentCongestionThreshold
+
+     // Only look for persistent congestion if the period
+     // starts after getting the first RTT sample.
+     assert(first_rtt_sample is not never)
+     if (largest_lost.time_sent - pc_period > first_rtt_sample):

FWIW, this is AllPacketsLost is not a fair representation of the algorithm in the latest PR.  Only the largest ack-eliciting packet is relevant, and the function needs to ensure that it only considers the first ack-eliciting packet.  But I guess we're abstracting over much of that.

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