IETF Logo Mail Archive

[iccrg] Feedback on draft-cheng-iccrg-delivery-rate-estimation-02

Junho Choi <junho.choi@gmail.com> Fri, 14 October 2022 21:13 UTC

Return-Path: <junho.choi@gmail.com>
X-Original-To: iccrg@ietfa.amsl.com
Delivered-To: iccrg@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 24719C15256A for <iccrg@ietfa.amsl.com>; Fri, 14 Oct 2022 14:13:22 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -7.105
X-Spam-Level:
X-Spam-Status: No, score=-7.105 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_HI=-5, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id pOQOes7W9_wt for <iccrg@ietfa.amsl.com>; Fri, 14 Oct 2022 14:13:18 -0700 (PDT)
Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 0644AC152568 for <iccrg@irtf.org>; Fri, 14 Oct 2022 14:13:18 -0700 (PDT)
Received: by mail-pj1-x1030.google.com with SMTP id gf8so6005445pjb.5 for <iccrg@irtf.org>; Fri, 14 Oct 2022 14:13:17 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=2PWmXJlM9o8XHI8e0lWaDgn5aGtRmjJIttqOGUdEfSA=; b=Dh66VIvJHkt7291ePdmAwtw1aQtGAfMzsG6Me1CTGsK3AnobvqjDVk18ClH71RwZBD 88HSeb/NPCgAlJnzBMFa8v8yh0Xqi6WmQQSWkuwOCfhGfLuPVf86i1P/krkClK2E5cb/ n/tlp83bXvook51QPmzZvECiASUeIVrhHPS7husxXrwd05Q056Ur0+xTOuXf/k/rbKS0 i0bsAUD5wrfKSnsOQuCRDmXqL/+K9AwijDPK8+79+8zsc/3WAZyvRosg2gGIekll90Er IiFcH8goBGYN5xCqmzdj19hP6hek7EEJd/ySXR7y+FZWT/Ewfcj1F1RftSysSBvCdIGX /vOA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=2PWmXJlM9o8XHI8e0lWaDgn5aGtRmjJIttqOGUdEfSA=; b=MGuZRyHcc7ZhsDnFnWpzSrizmCAv5x3Uw69E7SPQh0HpZ0eTc7wfSOnuXCcbzvXJla +1F4HYMr5gPOAn+I1HEZ0tHi7OfAt7HgM19GKixPJEpKZ1+lOyScvZ7yB4TyHmWGGUe4 X4wLPWWGMHOQysK5gYkvgdXu0jKj7XjQCq9zzm8e6wkSPqeEeBS4XwfXTg9JSDkjZpU3 KAJw4GNJsYydBgShkth92kdixL/6HX6Wr86v1pZuxJ0P1rvnUvpYrT20S8t8Y/qj40Ii jyhUfKeUmRDlGpykrzmElOcOALQA3y7moMdphi93ayWD3Pd0jTdy/0dmbnIiF1xHUOec eODg==
X-Gm-Message-State: ACrzQf0fAMRl/h60YPDABoz6svjPGuo2pAUaTvSYlAFrowHI4LYmMAYM u5s4/oXADgbgoBvOwg7MsKj5lV6xMgiw/vfAI2A=
X-Google-Smtp-Source: AMsMyM7wsM4kRVt0B6EKppQ8nIRnCc1zkB0udpMrziZC3T4BcEOrMhYq0Q9TA0Tz96cSAE51POn9gMnQSptG7+/a1QA=
X-Received: by 2002:a17:902:ce0d:b0:178:bd1e:e8da with SMTP id k13-20020a170902ce0d00b00178bd1ee8damr7196382plg.103.1665781997063; Fri, 14 Oct 2022 14:13:17 -0700 (PDT)
MIME-Version: 1.0
From: Junho Choi <junho.choi@gmail.com>
Date: Sat, 15 Oct 2022 06:12:40 +0900
Message-ID: <CAJ5e+HAX6VebtDoGKxb=cm1A27veK=wquE3=jdp=bkeG=Fx9dg@mail.gmail.com>
To: BBR Development <bbr-dev@googlegroups.com>, iccrg@irtf.org
Content-Type: multipart/alternative; boundary="00000000000035518205eb051846"
Archived-At: <https://mailarchive.ietf.org/arch/msg/iccrg/UwpLaPORHzHxZg14GL6EGgRqshQ>
Subject: [iccrg] Feedback on draft-cheng-iccrg-delivery-rate-estimation-02
X-BeenThere: iccrg@irtf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: "Discussions of Internet Congestion Control Research Group \(ICCRG\)" <iccrg.irtf.org>
List-Unsubscribe: <https://www.irtf.org/mailman/options/iccrg>, <mailto:iccrg-request@irtf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/iccrg/>
List-Post: <mailto:iccrg@irtf.org>
List-Help: <mailto:iccrg-request@irtf.org?subject=help>
List-Subscribe: <https://www.irtf.org/mailman/listinfo/iccrg>, <mailto:iccrg-request@irtf.org?subject=subscribe>
X-List-Received-Date: Fri, 14 Oct 2022 21:13:22 -0000

(I shared this report with the authors and they advised to share the
information with bbr-dev and iccrg, so posting here again)

While implementing this spec (the main purpose is to add BBR on quiche), I
think the following part needs some update.

> 3.2. Transmitting or retransmitting a data packet
> SendPacket(Packet P):

       if (SND.NXT == SND.UNA)  /* no packets in flight yet? */
         C.first_sent_time  = C.delivered_time = Now()

-->

       if (SND.NXT == SND.UNA)  /* no packets in flight yet? */
         C.first_sent_time  = C.delivered_time = P.sent_time

Looks like linux already doing the same logic:
https://elixir.bootlin.com/linux/v5.19.14/source/net/ipv4/tcp_rate.c#L59

I also made this change on quiche (
https://github.com/cloudflare/quiche/pull/1337) and got some good results
as well.

-- 
Junho Choi <junho dot choi at gmail.com> | https://saturnsoft.net

v2.23.0 | Report a Bug | By Email