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Re: [tcpm] [iccrg] Cwnd growth after fast convergence in CUBIC

Lars Eggert <lars@eggert.org> Fri, 06 November 2020 08:28 UTC

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From: Lars Eggert <lars@eggert.org>
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Date: Fri, 06 Nov 2020 10:28:16 +0200
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Cc: "Rosenblum, Wesley" <wesleyr=40amazon.com@dmarc.ietf.org>, "tcpm@ietf.org" <tcpm@ietf.org>, iccrg@irtf.org, Martin Thomson <mt@lowentropy.net>
To: Vidhi Goel <vidhi_goel=40apple.com@dmarc.ietf.org>
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Subject: Re: [tcpm] [iccrg] Cwnd growth after fast convergence in CUBIC
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Hi,

On 2020-11-6, at 6:45, Vidhi Goel <vidhi_goel=40apple.com@dmarc.ietf.org> wrote:
> IMO, we should not be applying beta to W_max after convergence factor has been applied in the K formula. Perhaps, it was an oversight in K’s formula.

the other authors of the CUBIC RFC are experts on the algorithm, I mostly just helped get it through the IETF process.

That said, the intent was to document what the Linux code was doing at the time. Is there a difference between the RFC and what Linux has been doing or is doing now? If yes, it might be time to revise the RFC.

(I think Martin Thomson also found some nits recently.)

Thanks,
Lars

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