Re: [tsvwg] Switch testing at 25G with ECN --SCE Draft

John Leslie <john@jlc.net> Fri, 09 August 2019 23:33 UTC

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Date: Fri, 9 Aug 2019 19:32:58 -0400
From: John Leslie <john@jlc.net>
To: Jonathan Morton <chromatix99@gmail.com>
Cc: tsvwg@ietf.org
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Subject: Re: [tsvwg] Switch testing at 25G with ECN --SCE Draft
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Jonathan Morton <chromatix99@gmail.com> wrote:
>> On 7 Aug, 2019, at 10:47 am, <Ruediger.Geib@telekom.de> <Ruediger.Geib@telekom.de> wrote:
>> 
>> I think to recall that a colleague noticed random initial packet drop
>> bursts with IPERF3 too (and stopped using it).
> 
> These are almost certainly associated with slow-start, whose
> exponential growth is that much harder to control than subsequent
> linear growth.

   It's kind of silly that each new TCP connection starts with the
assumption that it knows absolutely nothing about the likely capacity
and congestion of the route to its destination.

   Can't we do something to fix this?

--
John Leslie <john@jlc.net>