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

Jonathan Morton <chromatix99@gmail.com> Wed, 07 August 2019 22:39 UTC

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From: Jonathan Morton <chromatix99@gmail.com>
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Date: Thu, 8 Aug 2019 01:38:56 +0300
Cc: giuseppe.scaglione@hpe.com, tsvwg@ietf.org
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To: Ruediger.Geib@telekom.de
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Subject: Re: [tsvwg] Switch testing at 25G with ECN --SCE Draft
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> 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 not a fault in iperf, but a real phenomenon of TCP congestion control.

 - Jonathan Morton