IETF Logo Mail Archive

Re: [quicwg/base-drafts] unclear definition of persistent congestion (#3937)

Kazuho Oku <notifications@github.com> Wed, 22 July 2020 04:04 UTC

Return-Path: <noreply@github.com>
X-Original-To: quic-issues@ietfa.amsl.com
Delivered-To: quic-issues@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 5CB263A0C6C for <quic-issues@ietfa.amsl.com>; Tue, 21 Jul 2020 21:04:28 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.555
X-Spam-Level:
X-Spam-Status: No, score=-1.555 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_IMAGE_ONLY_20=1.546, HTML_MESSAGE=0.001, MAILING_LIST_MULTI=-1, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=github.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 ZgpneIHbxXM4 for <quic-issues@ietfa.amsl.com>; Tue, 21 Jul 2020 21:04:27 -0700 (PDT)
Received: from out-12.smtp.github.com (out-12.smtp.github.com [192.30.254.195]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E688F3A09DB for <quic-issues@ietf.org>; Tue, 21 Jul 2020 21:04:26 -0700 (PDT)
Received: from github-lowworker-a27607f.ash1-iad.github.net (github-lowworker-a27607f.ash1-iad.github.net [10.56.18.61]) by smtp.github.com (Postfix) with ESMTP id 9611C120FB4 for <quic-issues@ietf.org>; Tue, 21 Jul 2020 21:04:26 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=github.com; s=pf2014; t=1595390666; bh=ZOhgnui28avO2eXOVuW2fU2laU+/aH5OBvX9Kxfi6W4=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:List-ID: List-Archive:List-Post:List-Unsubscribe:From; b=Xx8+hsJPU39JeFtesznAH2dCFeEeCPma9qhMraROdSgKFNjJ3EAzo1wzs2VoIR0+q c1JNWOdk7YCF8NGoat2HzJvKA3fOZ+qWSYLGtDndxSk4vSnm8IW2LCMk6P/EPasHBE dnK3SvOselkgVDxwT6oyV4yBjvS3YBNtRHTbffw0=
Date: Tue, 21 Jul 2020 21:04:26 -0700
From: Kazuho Oku <notifications@github.com>
Reply-To: quicwg/base-drafts <reply+AFTOJK43RIRVZ3DUW7JFTZV5EON4VEVBNHHCPCXWJY@reply.github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Cc: Subscribed <subscribed@noreply.github.com>
Message-ID: <quicwg/base-drafts/issues/3937/662228692@github.com>
In-Reply-To: <quicwg/base-drafts/issues/3937@github.com>
References: <quicwg/base-drafts/issues/3937@github.com>
Subject: Re: [quicwg/base-drafts] unclear definition of persistent congestion (#3937)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5f17baca507bd_b163fa587ecd96812426"; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: kazuho
X-GitHub-Recipient: quic-issues
X-GitHub-Reason: subscribed
X-Auto-Response-Suppress: All
X-GitHub-Recipient-Address: quic-issues@ietf.org
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic-issues/spU9Hz64FZKv0XKPbvAgdHT_0bQ>
X-BeenThere: quic-issues@ietf.org
X-Mailman-Version: 2.1.29
List-Id: Notification list for GitHub issues related to the QUIC WG <quic-issues.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/quic-issues>, <mailto:quic-issues-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/quic-issues/>
List-Post: <mailto:quic-issues@ietf.org>
List-Help: <mailto:quic-issues-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/quic-issues>, <mailto:quic-issues-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 22 Jul 2020 04:04:28 -0000

Consider the case where the sender receives an acknowledgement for packets from 5 to 10, and the period between 1 and 4 was longer than 3*PTO. IIUC, this is clearly a persistent congestion.

The original example is strictly worse than that, and I think it would make sense to declare persistent congestion in the case too. In other words, I think that 3 is incorrect.

That said, I do not have a strong opinion regarding if we should specifically recommend either of 1 or 2, considering that the logic (or the time threshold) being used to detect persistent congestion is merely a recommendation.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/quicwg/base-drafts/issues/3937#issuecomment-662228692

v2.23.0 | Report a Bug | By Email