Re: [quicwg/base-drafts] Limit CWND increase in slow start (#3232)

Vidhi Goel <notifications@github.com> Thu, 14 November 2019 19:28 UTC

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Date: Thu, 14 Nov 2019 11:28:16 -0800
From: Vidhi Goel <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Limit CWND increase in slow start (#3232)
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goelvidhi commented on this pull request.



> @@ -1368,7 +1377,15 @@ acked_packet from sent_packets.
        return
      if (congestion_window < ssthresh):
        // Slow start.
-       congestion_window += acked_packet.size
+       if (pacing):
+         congestion_window += acked_packet.size
+       else:
+         // If pacing is not used, limit the increase to
+         // 2*max_datagram_size per ACK as described in
+         // {{?RFC3465}}
+         if (cwnd_increase < 2 * max_datagram_size):
+           cwnd_increase += bytes_acked
+           congestion_window += bytes_acked

@junhochoi could you give an example where it would be less than 2MSS?

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