Re: [quicwg/base-drafts] Set loss delay at least kGranularity (#2617)

ianswett <notifications@github.com> Mon, 15 April 2019 15:19 UTC

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Subject: Re: [quicwg/base-drafts] Set loss delay at least kGranularity (#2617)
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ianswett requested changes on this pull request.



> @@ -486,6 +486,12 @@ Using max(SRTT, latest_RTT) protects from the two following cases:
 * the latest RTT sample is higher than the SRTT, perhaps due to a sustained
   increase in the actual RTT, but the smoothed SRTT has not yet caught up.
 
+An endpoint might consistently record RTT samples as 0 in extremely low latency
+networks, leading to a smoothed_rtt of 0.  Consequently, the endpoint could
+declare all packets as lost immediately upon sending them.  To avoid declaring

This part isn't true.  There would still have to be reordering, since you need a later sent packet to be ACKed.

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