Re: [quicwg/base-drafts] Changing the Default QUIC ACK Policy (#3529)

Gorry Fairhurst <gorry@erg.abdn.ac.uk> Tue, 28 April 2020 11:37 UTC

Return-Path: <gorry@erg.abdn.ac.uk>
X-Original-To: quic@ietfa.amsl.com
Delivered-To: quic@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 6E5623A13B0 for <quic@ietfa.amsl.com>; Tue, 28 Apr 2020 04:37:27 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.896
X-Spam-Level:
X-Spam-Status: No, score=-1.896 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id oNMaHFyRFD48 for <quic@ietfa.amsl.com>; Tue, 28 Apr 2020 04:37:25 -0700 (PDT)
Received: from pegasus.erg.abdn.ac.uk (pegasus.erg.abdn.ac.uk [137.50.19.135]) by ietfa.amsl.com (Postfix) with ESMTP id 8FC363A13B2 for <quic@ietf.org>; Tue, 28 Apr 2020 04:37:23 -0700 (PDT)
Received: from GF-MacBook-Pro.local (fgrpf.plus.com [212.159.18.54]) by pegasus.erg.abdn.ac.uk (Postfix) with ESMTPSA id 1D8E41B0022B; Tue, 28 Apr 2020 12:37:19 +0100 (BST)
Subject: Re: [quicwg/base-drafts] Changing the Default QUIC ACK Policy (#3529)
To: QUIC WG <quic@ietf.org>
Cc: quicwg/base-drafts <reply+ABYLLEQELHT6VF64GKSQIKF4WLTRNEVBNHHCFSANWY@reply.github.com>, Lars Eggert <notifications@github.com>
References: <quicwg/base-drafts/issues/3529@github.com> <quicwg/base-drafts/issues/3529/620088318@github.com>
From: Gorry Fairhurst <gorry@erg.abdn.ac.uk>
Message-ID: <16fca907-e06f-d69a-f23d-a6c920c508ee@erg.abdn.ac.uk>
Date: Tue, 28 Apr 2020 12:37:18 +0100
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:68.0) Gecko/20100101 Thunderbird/68.7.0
MIME-Version: 1.0
In-Reply-To: <quicwg/base-drafts/issues/3529/620088318@github.com>
Content-Type: multipart/alternative; boundary="------------99C9DF204BC9437C0364A359"
Content-Language: en-GB
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic/9kdlUk6lil92cKh8bL6kbgcMmGU>
X-BeenThere: quic@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Main mailing list of the IETF QUIC working group <quic.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/quic>, <mailto:quic-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/quic/>
List-Post: <mailto:quic@ietf.org>
List-Help: <mailto:quic-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/quic>, <mailto:quic-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 28 Apr 2020 11:37:28 -0000

On 27/04/2020 17:19, Lars Eggert wrote:

> Folks who care about a change here need to prioritize progressing this 
> issue. We're close to being able to last-call the specs, and would 
> like this resolved in time.
>
> —
> You are receiving this because you authored the thread.
> Reply to this email directly, view it on GitHub 
> <https://github.com/quicwg/base-drafts/issues/3529#issuecomment-620088318>, 
> or unsubscribe 
> <https://github.com/notifications/unsubscribe-auth/ABYLLETADUCHE7WAN5IFIWDROWWBNANCNFSM4LOJ4RQA>.
>
We’ve completed a round of updated analysis of the proposed change to 
the QUIC spec, using quicly (changing to a 1:10 policy), and chromium 
(which currently does 1:10 by default). Our hope is that this change to 
the spec,  to actually make standard end-to-end QUIC work better than 
TCP over asymmetric paths!

This is a short slide deck about the performance of the proposed change:
https://erg.abdn.ac.uk/users/gorry/ietf/QUIC/QUIC-ack10-24-april-00.pdf

There have been a number of other change made by the QUIC ID editors 
relating to ACK processing, so we wanted to be sure these results were 
up to date. (These results do not consider additional ACKs after 
re-ordering - reflecting the latest text removing that.)

We also really hope this will motivate a change the practice of forcing 
of QUIC fallback to TCP (with PEP/Thining) over highly asymmetric paths. 
People may also be interested in work for L4S to evaluate the impact of 
ACK Thining for TCP-Prague.

Please do provide feedback, or any questions on this - as Lars notes, we 
think the time is running out for considering new changes, even 
relatively simple ones like this.

Gorry

P.S. First email: 
https://mailarchive.ietf.org/arch/msg/quic/NZBbuY88v0lrVspQE2A5br83asA/