Re: [quicwg/base-drafts] Limit CWND increase in slow start (#3232)

Jana Iyengar <notifications@github.com> Thu, 28 November 2019 11:52 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 46652120832 for <quic-issues@ietfa.amsl.com>; Thu, 28 Nov 2019 03:52:43 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -6.596
X-Spam-Level:
X-Spam-Status: No, score=-6.596 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, HTML_IMAGE_ONLY_28=1.404, HTML_MESSAGE=0.001, MAILING_LIST_MULTI=-1, RCVD_IN_DNSWL_HI=-5, 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 EpXW3Bv_hbz4 for <quic-issues@ietfa.amsl.com>; Thu, 28 Nov 2019 03:52:41 -0800 (PST)
Received: from out-24.smtp.github.com (out-24.smtp.github.com [192.30.252.207]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 80DEC12082E for <quic-issues@ietf.org>; Thu, 28 Nov 2019 03:52:41 -0800 (PST)
Received: from github-lowworker-b19c547.va3-iad.github.net (github-lowworker-b19c547.va3-iad.github.net [10.48.17.66]) by smtp.github.com (Postfix) with ESMTP id BC1DE6A0420 for <quic-issues@ietf.org>; Thu, 28 Nov 2019 03:52:40 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=github.com; s=pf2014; t=1574941960; bh=u4SyPp3/XtSl5FmPAneLs5s+B3RqM/Ukn3iHRD7OuQU=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:List-ID: List-Archive:List-Post:List-Unsubscribe:From; b=gqhgxKuA3rzUnoEe+aNd//qcZtE35NAUdmg+tLIpaEeekkyfRLiZVh9RT3Skp9FkQ +4bvlQ63O+7PYNAJQqM1rok0dMvSL8MTcXKqhpnG+jBjwmau8REutNLDO9ZUdzM13R 1Qyo1R/oICqD4bM2qxIPRcklkiLMzrNL4ZJAbzpw=
Date: Thu, 28 Nov 2019 03:52:40 -0800
From: Jana Iyengar <notifications@github.com>
Reply-To: quicwg/base-drafts <reply+AFTOJK5RYZYZ7ITXVJXIC5N35TTYREVBNHHB6GTRAA@reply.github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Cc: Subscribed <subscribed@noreply.github.com>
Message-ID: <quicwg/base-drafts/pull/3232/review/324237069@github.com>
In-Reply-To: <quicwg/base-drafts/pull/3232@github.com>
References: <quicwg/base-drafts/pull/3232@github.com>
Subject: Re: [quicwg/base-drafts] Limit CWND increase in slow start (#3232)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5ddfb508acff8_75e13fdc6dacd9681103366"; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: janaiyengar
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/Nfhw-GHOXQLyEsWz_kdpShnpHOE>
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: Thu, 28 Nov 2019 11:52:43 -0000

janaiyengar commented on this pull request.



> @@ -769,7 +769,10 @@ Implementations MUST either use pacing or limit such bursts to the initial
 congestion window, which is recommended to be the minimum of
 10 * max_datagram_size and max(2* max_datagram_size, 14720)), where
 max_datagram_size is the current maximum size of a datagram for the connection,
-not including UDP or IP overhead.
+not including UDP or IP overhead. An implementation that does not use pacing
+SHOULD limit the congestion window increase during slow start to

We've already said that a sender MUST limit bursts to IW, so there's no reason to repeat that. I would argue this is a SHOULD-level requirement; MAY is strange, since that's really a permission and that's not what we're going after here. I'd suggest dropping the phrase "in order to limit bursts" --- "An implementation that does not use pacing SHOULD limit the congestion window increase during slow start to 2 * max_datagram_size per ACK frame received {{?RFC3465}}. "

-- 
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/pull/3232#discussion_r351739490