From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) (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 D661C3B29E; Sun, 7 Aug 2022 00:29:08 -0400 (EDT) Received: by mail-pj1-x102b.google.com with SMTP id e8-20020a17090a280800b001f2fef7886eso6342165pjd.3; Sat, 06 Aug 2022 21:29:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc; bh=WOJTCyAp8lgMP7fsdm0QE4suenHFe+Fx2cQVVQSHEeE=; b=W0eifOos3RJ4YWgZqFoGmS3pAknXzgA0E0B5mbakDTGprEKiHASdP6T2eRiPU3vbL/ xb7LTDLUxveOLwtFSHIg6pRgAYa8rphASi7047d82GKYN5Fza9LimMAEhK8iErj2wjmn NfiYxDPgCMx6LxN5pZAWAVxKnJsXhJyX7wU2O/lyIJywAadlWGRYf0RRObW+/AQEaJBC jF+gTBV/qI/5tnmEtiGO7o2J90016vNwWkbhF22gS+QGuomRINqyf+hQ7Ubc7ZlDVN/n l6GDKpXDFgJ+vxcsX0/5UNPhuPlJfxGGABcXA6oHShvhyyzOkyyfUfdy+b/YU86DL3WF 4RfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=WOJTCyAp8lgMP7fsdm0QE4suenHFe+Fx2cQVVQSHEeE=; b=bkywtwOq87k0Spfbsve/WDONtruCATOvOXMbhrFzXSD1Qq6BNmFbEGCrjwwKA72Ubm k0l4iRqV9qRKwgG1fbQ6rYJgcPS36Cr8FqtdMGtKjUd/E8KB9c6co7hUQpUVfqJ4FUf6 DFS9sDkhhlzTbZU3VqZ1IVjujl+wRW+95GTP/MzQbQds1ScLEiITK5IqaYKDkbmF8Pz9 M5McIOt6goAXJjUpfUFzXfMwWHxbs+NOZ1qBf3nhS9mZ1sA5zMl2bp/YhvhnTJAZkmj2 ZFBLjNli1OlQLp7mhBHiPvYoVCT4Zmn+1rricLT7w/E1jkEM2+1tyhhJQreLM1c2YiHw svOw== X-Gm-Message-State: ACgBeo2ivP3BkaiO69o7RTwCngtm61S/R+PM/vt9n9azDooYSlNIksXj SCNc0I8oTvLoDZNLuPBNZgRSkr2OWV/FfShMncc= X-Google-Smtp-Source: AA6agR7SHI4WxwV6uB6jzqRtfOqp1DeMZ2NA0T9A4j+Hak/irUpolYznhHq3OwIkhUoiDMEV2KKNz8ni97QbbXgQRVo= X-Received: by 2002:a17:90a:7885:b0:1f2:1825:ae7e with SMTP id x5-20020a17090a788500b001f21825ae7emr14734654pjk.39.1659846547638; Sat, 06 Aug 2022 21:29:07 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Venkat Arun Date: Sun, 7 Aug 2022 09:58:31 +0530 Message-ID: To: Dave Taht Cc: bloat , BBR Development , Dave Taht via Starlink , venkatar@csail.mit.edu, Mohammad Alizadeh , Hari Balakrishnan Content-Type: multipart/alternative; boundary="000000000000da8cf305e59f238e" X-Mailman-Approved-At: Sun, 07 Aug 2022 08:31:17 -0400 Subject: Re: [Bloat] SIGCOMM MIT paper: Starvation in e2e congestion control 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: Sun, 07 Aug 2022 04:29:09 -0000 --000000000000da8cf305e59f238e Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Dave, Yes definitely, when fair-queuing is present, the onus is no longer on the congestion control algorithm to ensure fairness. In fact, if buffer-sharing is implemented correctly, FQ can even stand against adversarial congestion control algorithms. We have good reason to believe that end-to-end congestion control algorithms can provably work (i.e. achieve high utilization, bounded delay and fairness) in the presence of FQ. Cheers, Venkat On Fri, Aug 5, 2022 at 12:36 AM Dave Taht wrote: > Perhaps it's obvious to the authors that FQ opens up new possibilities > for delay based convergence. Otherwise, pretty good: > > "We prove that when two flows using the same CCA share a bottleneck > link, if the non-congestive delay variations exceed double the > difference between the maximum and minimum queueing delay at > equilibrium, then there are patterns of non-congestive delay where one > flow will get arbitrarily low throughput compared to the other. Our > theorem shows that CCAs have > to choose at most two out of three properties: high through put, > convergence to a small and bounded delay range, and no starvation." > > Paper: http://people.csail.mit.edu/venkatar/cc-starvation.pdf > > Article: > https://news.mit.edu/2022/algorithm-computer-network-bandwidth-0804 > > > > -- > FQ World Domination pending: > https://blog.cerowrt.org/post/state_of_fq_codel/ > Dave T=C3=A4ht CEO, TekLibre, LLC > --000000000000da8cf305e59f238e Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Dave,

Yes definitely, whe= n fair-queuing is present, the onus is no longer on the congestion control = algorithm to ensure fairness. In fact, if buffer-sharing is implemented cor= rectly, FQ can even stand against adversarial congestion control algorithms= . We have good reason to believe that end-to-end congestion control algorit= hms can provably work (i.e. achieve high utilization, bounded delay and fai= rness) in the presence of FQ.

Cheers,
Venkat

On Fri, Aug 5, 2022 at 12:36 AM Dave Taht <dave.taht@gmail.com> wrote:
Perhaps it's obvious to = the authors that FQ opens up new possibilities
for delay based convergence. Otherwise, pretty good:

"We prove that when two flows using the same CCA share a bottleneck link, if the non-congestive delay variations exceed double the
difference between the maximum and minimum queueing delay at
equilibrium, then there are patterns of non-congestive delay where one
flow will get arbitrarily low throughput compared to the other. Our
theorem shows that CCAs have
to choose at most two out of three properties: high through put,
convergence to a small and bounded delay range, and no starvation."
Paper: http://people.csail.mit.edu/venkatar/cc= -starvation.pdf

Article: https://news.mit.edu/202= 2/algorithm-computer-network-bandwidth-0804



--
FQ World Domination pending: https://blog.cerowrt.or= g/post/state_of_fq_codel/
Dave T=C3=A4ht CEO, TekLibre, LLC
--000000000000da8cf305e59f238e--