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Re: [quicwg/base-drafts] Clarify OnAckReceived pseudocode (#2140)

Benjamin Saunders <notifications@github.com> Tue, 18 December 2018 18:20 UTC

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Subject: Re: [quicwg/base-drafts] Clarify OnAckReceived pseudocode (#2140)
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Ralith commented on this pull request.



> @@ -716,6 +717,9 @@ Pseudocode for OnAckReceived and UpdateRtt follow:
 
 ~~~
   OnAckReceived(ack):
+    largest_acked_packet = max(largest_acked_packet,

> you MAY use the largest acked from the most recent ACK, which could reduce spurious retransmits when one packet arrives far out of order

Any reason not to make this the sole recommendation? I had some trouble coming up with a case where that might occur, which is why I didn't take that route originally, but I think I see it now: when a reordered ACK newly acknowledges a packet such that the newly acknowledged packet is > ack.largest_acked - kPacketThreshold, but <= largest_acked_packet - kPacketThreshold.

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