Re: [quicwg/base-drafts] Only send one immediate ACK after reordering (#3357)

Gorry Fairhurst <notifications@github.com> Mon, 03 February 2020 15:26 UTC

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Date: Mon, 03 Feb 2020 07:26:18 -0800
From: Gorry Fairhurst <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Only send one immediate ACK after reordering (#3357)
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My point is I think this is the wrong direction. I think n=2 is unnecessarily restrictive as a default, and does have unwanted performance impacts in some places. 

I think the case of loss for a burst of one packet that you mention is handed by the timer. The congestion impact is minor.

While I agree for n=2 the method doesn't make much difference, for n=10, it would make a difference - because I'd expect it to be Important to be able to robustly detect and respond after congestion, I'm not sure it matters if the intention is to send DupACK+k immediate ACks or to send ACKs more frequently for some proportion of a RTT. 

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