Re: [quicwg/base-drafts] Reduce restrictions on valid RTT samples (#2568)

Nick Banks <> Sat, 30 March 2019 23:52 UTC

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From: Nick Banks <>
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Subject: Re: [quicwg/base-drafts] Reduce restrictions on valid RTT samples (#2568)
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It just seems like a bad idea to always ignore RTT measurements if ack_delay is larger than max_ack_delay. For instance, what about one of the following scenarios:

1. Sheer CPU load on the peer prevents it from ACK'ing a packet within max_ack_delay.
2. An implementation that literally sets a max_ack_delay timer on receipt of a packet, then when the timer fires, queues a send packet work item. When that work item is processed, the ack_delay is calculated and it ends up being just over max_ack_delay.

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