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Re: [quicwg/base-drafts] Reduce restrictions on valid RTT samples (#2568)

ianswett <notifications@github.com> Tue, 02 April 2019 19:03 UTC

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Subject: Re: [quicwg/base-drafts] Reduce restrictions on valid RTT samples (#2568)
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@nibanks In both cases, I believe the current algorithm of limiting ack_delay to max_ack_delay makes perfect sense.  In the case of CPU load, RTT should show up in SRTT, RTTVar, or both.

In the second case, the text also advises including any expected timer delay in your advertised max_ack_delay.

This issue is about what happens if the largest acked is an ACK-only packet(not ack-eliciting).  In this case, we do ignore the RTT sample, and I do think that could turn out to be problematic, particularly in very asymmetric flows.

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