From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id AB9673CB35 for ; Mon, 6 Jul 2020 10:09:08 -0400 (EDT) Received: by mail-wr1-x42b.google.com with SMTP id b6so41084576wrs.11 for ; Mon, 06 Jul 2020 07:09:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ieee.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ReaRguURUNQZPFpEadTo3r9AzH/gwHPki59L832QY18=; b=bceN8gPoSYaWgHTz8mss3Z7BKw6fBlrMrHRlnSIlJ5YbQI1aoM81PBdda8tzUZmeR9 tt8NFgA1kvAiQvTJjNwdkogGT9DT4GRguIzK5ytLRQVzX4eIKRgJ6FyVcXxsCFSYXod3 2XI17ZZjMfw39FwwE/JCaRorOZW9gjja3AmJ4= 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=ReaRguURUNQZPFpEadTo3r9AzH/gwHPki59L832QY18=; b=VAQF3/iZ8iwzrI5HvaLPGC4BHgxIWtSRzwc5LLTocgVh1d3e8rTbZBmW7ij3qmGs5n DuovMQ8slUotWluRmWLlwX0ZAD5YTE3hUmirFPqlY0vtH9Phk4U8RwEK15EFa6Hv7X/i KyeTkvQQODPn7zekjCUHqQqAe94VfcAtQgyP7Bm9AEPV0tefDkPfuXrCD9xGao9+uWov G3DcPMbmk8L5rq0ezkhJz58FQJwXI9oldK+Jj/Fl5QmX+WYPwNGXSx61h+wI2T1pVDpK lwtaVwFtX8fklyKNTqx85ZzToSVQS6fICj+vjhjXsjteuFQOv1q50LWmlskNNdsQ6ZJ0 c2MA== X-Gm-Message-State: AOAM532g3q9vyfBbJsBl2CeXETFbWlFdUiHiWiOykdlmneRGG0/hioNx mZ+jmNtNO7s1omyzBbNuGkLB6dLL9boTe8Z643vIGQ== X-Google-Smtp-Source: ABdhPJzISb3a+ObWonBgTX3KyeKSJTtstnhypg9QfBK4W9ga5bDZLeIFYkyedIIThIjaV1PGnHJZlLjGQCmMO5vE7Rs= X-Received: by 2002:adf:9286:: with SMTP id 6mr49315565wrn.361.1594044547619; Mon, 06 Jul 2020 07:09:07 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Luca Muscariello Date: Mon, 6 Jul 2020 16:08:56 +0200 Message-ID: To: Dave Taht Cc: Carlo Augusto Grazia , Make-Wifi-fast , jamshid@whatsapp.com, bloat Content-Type: multipart/alternative; boundary="00000000000004855b05a9c66ba4" Subject: Re: [Bloat] [Make-wifi-fast] the future belongs to pacing X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Jul 2020 14:09:08 -0000 --00000000000004855b05a9c66ba4 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable It is not surprising that BBR comes from Van who's also designed and implemented pathchar. I liked reading the paper when it was published and it has the merit to be simple to read for a large audience. I agree very much on the title as bang-bang congestion control (not only AIMD) could be deprecated entirely by measurement based approaches like BBR. In bang-bang cc the sending rate is obtained by a root-finding algorithm (gradient based) that is fed by measurements of congestion (queue, loss, latency), whereas in BBR the sending rate is an (almost?) explicit function of the measured quantities. In theory both approaches work, but for the former we have seen a proliferation of root-finding algorithms for wireless, large BDP networks, small BDP network, satellite, cellular, shared-media, non-shared media and more. Selection of the right one is a question of tuning, which is extremely complex and static. If BBR can fix that by having a unique model for all these cases that would make deprecation, as intended in the paper, likely to happen. On Fri, Dec 13, 2019 at 10:25 PM Dave Taht wrote: > and everything we know about the tcp macroscopic model, is obsolete, > according to a provocative paper by matt mathis and Jamshid Mahdavi > in sigcomm. > > https://ccronline.sigcomm.org/wp-content/uploads/2019/10/acmdl19-323.pdf > > > > > On Fri, Dec 13, 2019 at 1:05 PM Carlo Augusto Grazia > wrote: > > > > Hi Dave, > > thank you for your email! > > Toke told me about AQL a couple of weeks ago, I definitely want to test > it ASAP. > > BBR struggles a lot on Wi-Fi interfaces (ones with aggregation) with > kernel 4.14 & 4.19. > > Anyway, it seems that with BBRv2 on new kernels this problem does not > exist anymore. > > > > Best regards > > Carlo > > > > Il giorno ven 13 dic 2019 alle 20:54 Dave Taht ha > scritto: > >> > >> https://sci-hub.tw/10.1109/WiMOB.2019.8923418 > >> > >> It predates the aql work, but the bbr result is puzzling. > >> > >> > >> -- > >> Make Music, Not War > >> > >> Dave T=C3=A4ht > >> CTO, TekLibre, LLC > >> http://www.teklibre.com > >> Tel: 1-831-435-0729 > > > > -- > > -------------------------------------------------------------------- > > Carlo Augusto Grazia, Ph. D. > > Assistant Professor > > -------------------------------------------------------------------- > > Dept. of Engineering "Enzo Ferrari" > > University of Modena and Reggio Emilia > > Via Pietro Vivarelli, 10/1 - 41125 - Modena - Italy > > Building 26, floor 2, room 28 > > Tel.: +39-059-2056323 > > email: carloaugusto.grazia@unimore.it > > Link to my personal home page here > > -------------------------------------------------------------------- > > > > -- > Make Music, Not War > > Dave T=C3=A4ht > CTO, TekLibre, LLC > http://www.teklibre.com > Tel: 1-831-435-0729 > _______________________________________________ > Make-wifi-fast mailing list > Make-wifi-fast@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/make-wifi-fast --00000000000004855b05a9c66ba4 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
It is not surprising that BBR comes from Van who's also designed and= implemented pathchar.

I liked reading the paper when it was published and it has the me= rit to be simple to read
for a large audience.

I agree very much on the title as bang-bang cong= estion control (not only AIMD) could be
deprecated entirely by measurement based app= roaches like BBR.=C2=A0=C2=A0

In bang-bang cc the sending rate is obtained by a root-fin= ding algorithm (gradient based) that
is fed by measurements of congestion (queue, lo= ss, latency), whereas in BBR the sending rate is
an (almost?) explicit function of t= he measured quantities.=C2=A0

In theory both approaches=C2=A0work, but for the former we= have seen a proliferation of root-finding algorithms
for wireless, large BDP networ= ks, small BDP network, satellite, cellular, shared-media, non-shared media = and more.
Selection of the right one is a question of tuning, which is extremely com= plex and static.

If BBR can fix that by having a unique model for all these cases that= =C2=A0would make deprecation, as intended in the paper,
likely to happen.

On Fri, D= ec 13, 2019 at 10:25 PM Dave Taht <dave.taht@gmail.com> wrote:
and everything we know about the tcp macroscopic model= , is obsolete,
according to a=C2=A0 provocative paper by matt mathis and Jamshid Mahdavi in sigcomm.

https://ccronline.sigcomm.or= g/wp-content/uploads/2019/10/acmdl19-323.pdf




On Fri, Dec 13, 2019 at 1:05 PM Carlo Augusto Grazia
<car= loaugusto.grazia@unimore.it> wrote:
>
> Hi Dave,
> thank you for your email!
> Toke told me about AQL a couple of weeks ago, I definitely want to tes= t it ASAP.
> BBR struggles a lot on Wi-Fi interfaces (ones with aggregation) with k= ernel 4.14 & 4.19.
> Anyway, it seems that with BBRv2 on new kernels this problem does not = exist anymore.
>
> Best regards
> Carlo
>
> Il giorno ven 13 dic 2019 alle 20:54 Dave Taht <dave.taht@gmail.com> ha scritt= o:
>>
>> https://sci-hub.tw/10.1109/WiMOB.2019.8923418<= /a>
>>
>> It predates the aql work, but the bbr result is puzzling.
>>
>>
>> --
>> Make Music, Not War
>>
>> Dave T=C3=A4ht
>> CTO, TekLibre, LLC
>> http://www.teklibre.com
>> Tel: 1-831-435-0729
>
> --
> -------------------------------------------------------------------- > Carlo Augusto Grazia, Ph. D.
> Assistant Professor
> -------------------------------------------------------------------- > Dept. of Engineering "Enzo Ferrari"
> University of Modena and Reggio Emilia
> Via Pietro Vivarelli, 10/1 - 41125 - Modena - Italy
> Building 26, floor 2, room 28
> Tel.: +39-059-2056323
> email: carloaugusto.grazia@unimore.it
> Link to my personal home page here
> --------------------------------------------------------------------


--
Make Music, Not War

Dave T=C3=A4ht
CTO, TekLibre, LLC
ht= tp://www.teklibre.com
Tel: 1-831-435-0729
_______________________________________________
Make-wifi-fast mailing list
M= ake-wifi-fast@lists.bufferbloat.net
https://lists.bufferbloat.net/listinfo/make-wif= i-fast
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