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

ianswett <notifications@github.com> Wed, 08 May 2019 01:32 UTC

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

There are congestion controllers now, and hopefully more in the future, that operate primarily pacing limited, not CWND limited, so this was an effort to capture that, but it's certainly imperfect.  Any suggestions?

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