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Re: [quicwg/base-drafts] Reset min_rtt on persistent congestion (#3927)

Martin Thomson <notifications@github.com> Thu, 23 July 2020 04:50 UTC

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Date: Wed, 22 Jul 2020 21:50:48 -0700
From: Martin Thomson <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Reset min_rtt on persistent congestion (#3927)
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I think that's OK.  In practice, immediate ACKs do happen, and even at low rates, this should resolve to a "true" minimum.  And if it doesn't, then you have worse performance than you might had otherwise.  You have to have a pretty poor network (or a terrible ACK generation regime) for min_rtt not to eventually resolve to a useful minimum.

Explaining this risk is fine, but the endpoint that does this made the choice to throw out min_rtt and that's just a consequence of that.

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