IETF Logo Mail Archive

Re: Proposed extension for delayed acknowledgments

Jana Iyengar <jri.ietf@gmail.com> Fri, 24 January 2020 00:08 UTC

Return-Path: <jri.ietf@gmail.com>
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 B9525120091 for <quic@ietfa.amsl.com>; Thu, 23 Jan 2020 16:08:47 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.997
X-Spam-Level:
X-Spam-Status: No, score=-1.997 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
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 ABCC_QWr6s3j for <quic@ietfa.amsl.com>; Thu, 23 Jan 2020 16:08:45 -0800 (PST)
Received: from mail-lj1-x234.google.com (mail-lj1-x234.google.com [IPv6:2a00:1450:4864:20::234]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id EE83C120041 for <quic@ietf.org>; Thu, 23 Jan 2020 16:08:44 -0800 (PST)
Received: by mail-lj1-x234.google.com with SMTP id y4so376186ljj.9 for <quic@ietf.org>; Thu, 23 Jan 2020 16:08:44 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=xuzmqeJ4OhMBGEKqQUbVIdb+gTO98gHRjwxgabj5oME=; b=jESDXI1a3hTisz8+exsTxIDyCcAPRtRQaCJgZCspkxrvGF/f3ABGTjMUW6P53E5w6B vpzl1+GqsC789WNDU71ErLAMQq2VWhqa3nmKu3PQC6KN+p8xDUhcC65zDjj8ca1jicsY fwr09iQyme1Sha+ASHzdOHYS+HEPDLXWZ5YXUA6EZfWZ0/nJktC/HxQ/Sqi8OC3DAyx5 9Z3PVhQK47f+tPqA6ejeJ6LpsTAoDaGvlUvxri8PC5AOH+GR5nmOATVcHjEM6r9ENzh6 YENpCxwf0POx4m1SP3l22wf2/gsQuv9GFLidGTngMST5xrLAZxhAxzWE+URrdpRgYYk2 CInA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=xuzmqeJ4OhMBGEKqQUbVIdb+gTO98gHRjwxgabj5oME=; b=mTp5B1QDpcxh4vorSJCwCvE/9erlCY5CQAjQ5Yc+zwqif85FctnVQVKfdT2HapzmT/ aVl01tcM8JZSO52KbTjnCo+s0GfeVwPHTRHfbEo448BvKwO277gMvNlwlVJloup42U2g 5VGSvyXskG/CNc0PBxwQQ7v3bdmVa9wW85GwC593yUAlys/C6iVUnYjmFzAl9yOVLh9+ 7TvWD85JjzXBR4EmZ1qIGtq3/Zs34Luz2/msGWGH2rJqc5B/kX4jT8UmMxG9QSvm6oVU B8yBTApOFb0WHc9hbhDvK97kPtfwmmgW++nRNCbWtGNI5GWhDIvKopQWhg4mhoIGFkaK UoXQ==
X-Gm-Message-State: APjAAAWvJXB4CjPZGdBKHBV7xnBVwIdQ/4ad2adfm4pdAT/2Gk+NYTD3 039cQV/NNwjVhayOv8N96c7HmbqkpwUNfiBOne4=
X-Google-Smtp-Source: APXvYqwq86nuYu9EymuMir7bEMdeb6DWKRJqm6FCqYyN8Dy760bloxMm6YVOIChr11wO5LisgsRLizK+IOZk8ilDu7Q=
X-Received: by 2002:a2e:2201:: with SMTP id i1mr560144lji.110.1579824521969; Thu, 23 Jan 2020 16:08:41 -0800 (PST)
MIME-Version: 1.0
References: <CACpbDcdaGPZN1MpxE8GRV64dO8OK64xbCoUvxHPmCoCk9R-MOg@mail.gmail.com> <CAKcm_gNWXn_binsbcxkpzB8pFy+tEU7ZJ2CvGSCtnEKHNqN8Jg@mail.gmail.com> <CADdTf+iMwjodXccWkfOTOQe6ahFNPK4bFZ5v5tpk1oqO0f4Pdw@mail.gmail.com> <e4e41020-9416-7549-5f0e-3c36cc0c0947@huitema.net>
In-Reply-To: <e4e41020-9416-7549-5f0e-3c36cc0c0947@huitema.net>
From: Jana Iyengar <jri.ietf@gmail.com>
Date: Thu, 23 Jan 2020 16:08:31 -0800
Message-ID: <CACpbDceZioL3yUB9QWCgciEGKqwcubwd_JBN2EW2=X3+66hYyA@mail.gmail.com>
Subject: Re: Proposed extension for delayed acknowledgments
To: Christian Huitema <huitema@huitema.net>
Cc: Matt Joras <matt.joras@gmail.com>, Ian Swett <ianswett=40google.com@dmarc.ietf.org>, QUIC WG <quic@ietf.org>
Content-Type: multipart/alternative; boundary="00000000000070833b059cd78f03"
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic/a9RtupH5xjifhjJtFVmvWr7FQAQ>
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: Fri, 24 Jan 2020 00:08:48 -0000

Christian,

No, that would be silly :-) There are exceptions allowed at a receiver --
such as when the receiver receives a batch of packets -- and we have to
allow for such things to happen. Also, ack loss, late timers, scheduler
delays, are all things that can cause a receiver to not follow the schedule
exactly. That's ok.

- jana

On Thu, Jan 23, 2020 at 3:53 PM Christian Huitema <huitema@huitema.net>
wrote:

> On 1/23/2020 12:25 PM, Matt Joras wrote:
>
> Thank you Jana and Ian for doing this!
>
> As I noted on #3304, we have also observed this sort of change is critical
> to reducing client-originated ACK traffic for typical Internet content, and
> for CPU performance of both client and server. Noting here that I have
> opened an issue (#17
> <https://github.com/janaiyengar/ack-frequency/issues/17>) for the
> following: given that we have a basic heuristic that seems to work pretty
> well for multiple deployments (default behavior for first 100 packets,
> packet tolerance of 10 after), do we want to make that recommendation
> explicit in the extension itself?
>
> +1
>
> Also, I am a bit concerned of the slippery slope there. Suppose a peer
> receives a frame that says "only every 22 packets please". Are we going to
> flag a protocol violation if the receiver acks after 23 packets? Or 10? Or
> 1?
>
> -- Christian Huitema
>

v2.23.0 | Report a Bug | By Email