Re: [quicwg/base-drafts] !editorial: simplify pseudo code (recovery) (#3384)

mirjak <notifications@github.com> Thu, 23 January 2020 09:46 UTC

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Subject: Re: [quicwg/base-drafts] !editorial: simplify pseudo code (recovery) (#3384)
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mirjak commented on this pull request.



> @@ -346,9 +346,7 @@ On subsequent RTT samples, smoothed_rtt and rttvar evolve as follows:
 
 ~~~
 ack_delay = min(Ack Delay in ACK Frame, max_ack_delay)
-adjusted_rtt = latest_rtt
-if (min_rtt + ack_delay < latest_rtt):
-  adjusted_rtt = latest_rtt - ack_delay
+adjusted_rtt = max(latest_rtt - ack_delay, min_rtt)

Ups, yes, you are right. I think I got that impression from reading "MUST NOT apply the adjustment if the resulting RTT sample is smaller than the min_rtt", however, that's not what it says.

I think changing the if to the following would be slightly more readable for me but doesn't make a big difference:

if (latest_rtt - ack_delay > min_rtt):

Or even

 adjusted_rtt = latest_rtt  - ack_delay
 if (adjusted_rtt > min_rtt):
   adjusted_rtt = latest_rtt

However, we can also just withdraw this PR.

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