Re: [quicwg/base-drafts] Limit CWND increase in slow start (#3232)

ianswett <notifications@github.com> Wed, 13 November 2019 00:26 UTC

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Subject: Re: [quicwg/base-drafts] Limit CWND increase in slow start (#3232)
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Thanks for your PR, it's helpful to see this clarified.

I think it's worth a discussion of two issues, maybe in Singapore:
1) Do we need anything in addition to the existing IW burst limit?  A single ACK loss would not cause a burst to exceed the IW10 limit, and multiple consecutive ACK losses in slow start are VERY rare in my experience.
2) Do we need to describe the non-pacing scenarios in the pseudocode, given we recommend pacing?  Using CWND to manipulate sending behavior is an indirect method that feels like a holdover from implementation details of older TCP algorithms to me.

I'm no on both counts currently, but if the WG feels otherwise, I can accept that.

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