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

Vidhi Goel <notifications@github.com> Tue, 12 November 2019 22:25 UTC

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Date: Tue, 12 Nov 2019 14:25:31 -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 +1377,14 @@ 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

It is only used to limit the increase to 2*MSS in slow start

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