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Date: Wed, 29 Nov 2017 15:31:30 +0100 (CET)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Luca Muscariello <luca.muscariello@gmail.com>
cc: Sebastian Moeller <moeller0@gmx.de>, bloat <bloat@lists.bufferbloat.net>
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Subject: Re: [Bloat] benefits of ack filtering
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On Wed, 29 Nov 2017, Luca Muscariello wrote:

>> Why does it say to do this? What benefit is there to either end system to
>> send 35kPPS of ACKs in order to facilitate a 100 megabyte/s of TCP transfer?
>
> Did you check RFC 3449 ?
> https://tools.ietf.org/html/rfc3449#section-5.2.1

RFC3449 is all about middleboxes doing things.

I wanted to understand why TCP implementations find it necessary to send 
one ACK per 2xMSS at really high PPS. Especially when NIC offloads and 
middleboxes frequently strip out this information anyway so it never 
reaches the IP stack (right?).

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se