Re: [quicwg/base-drafts] Persistent congestion interaction with app limited state (#2593)

Subodh Iyengar <> Fri, 12 April 2019 23:55 UTC

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Subject: Re: [quicwg/base-drafts] Persistent congestion interaction with app limited state (#2593)
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Ya i think that's a decent mitigation there. The text assumes an implementation that keeps the PTO armed even if there is a packet outstanding that does not have new or expired data. In our case we don't arm the timer when there is a packet with no new data. The assumption that the spec makes is that if you have outstanding packets to send you have outstanding data, however we explicitly check whether we have outstanding data to send rather than using outstanding packets as a proxy.

Oh now that you brought up PTO, I'm thinking about what would happen if data was being sent slowly, that is if data is sent just before PTO expires and in response to new requests which are trickling in. Is the intent of persistent congestion here to mark this case as persistent congestion as well?

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