Re: [tcpm] Better QoS for TCP ACK question

Toerless Eckert <tte@cs.fau.de> Mon, 16 April 2018 16:45 UTC

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Date: Mon, 16 Apr 2018 18:45:13 +0200
From: Toerless Eckert <tte@cs.fau.de>
To: Gorry Fairhurst <gorry@erg.abdn.ac.uk>
Cc: Mikael Abrahamsson <swmike@swm.pp.se>, tcpm@ietf.org
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Subject: Re: [tcpm] Better QoS for TCP ACK question
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On Mon, Apr 16, 2018 at 04:42:12PM +0100, Gorry Fairhurst wrote:
> Just to send something more to this list thread:
> 
> RFC 3449 from 2002 describes this in section 5.4.2 on ACKs-first Scheduling.

Ah, great. Thanks. Something to point people to. 

> I aware this method was implemented in a variety of equipment around that
> time, although I suspect it can also cause some odd performance hits when
> using app-limited TCP sessions (where many data segments are also small and
> may also become reordered).
> Gorry

I guess this would refer not to an actual TCP-ACK DPI based
scheduling that you could easily do on CPU processing home
gateways, but rather the packet-length based queuing Mikael
brought up ? Otherwise i don't understand.

Toerless