Re: [quicwg/base-drafts] Define under-utilizing the congestion window (#2675)

Jana Iyengar <> Thu, 17 October 2019 21:23 UTC

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Subject: Re: [quicwg/base-drafts] Define under-utilizing the congestion window (#2675)
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janaiyengar commented on this pull request.

> @@ -836,9 +836,11 @@ in Linux (3.11 onwards).
 ## Under-utilizing the Congestion Window
-A congestion window that is under-utilized SHOULD NOT be increased in either
-slow start or congestion avoidance. This can happen due to insufficient
-application data or flow control credit.
+When bytes in flight is smaller than the congestion window and sending is not
+pacing limited, the congestion window is under-utilized.  When this occurs,

@junhochoi : The point here is that if you're unable to utilize the full cwnd because you are limited by a pacer, then it doesn't count as app limited.

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