From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa1-x31.google.com (mail-oa1-x31.google.com [IPv6:2001:4860:4864:20::31]) (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 1D6BD3B29E for ; Fri, 31 Jan 2025 18:57:50 -0500 (EST) Received: by mail-oa1-x31.google.com with SMTP id 586e51a60fabf-2b2b6019a74so1201534fac.0 for ; Fri, 31 Jan 2025 15:57:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1738367869; x=1738972669; darn=lists.bufferbloat.net; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=S/RN568Fmuvl8ZzV1YDesmJM5KfuLeOghoyLrEkHA3k=; b=fCcNSsIjQQMqg3Pkt8quFjD6kNIGqgZGXpOHxjbAxzPJgj6kvU0jsyfVJIiElzBj07 QSJV+lPYqX3i73ExcMid7Qskb4a16fd1wTvnBnVWKsF+js5KyODxKQTkXplE7uVi6q9O R8q/gk8Nk2x94JNcIEhCPGq4mGh69gu6+sy26pc35uOxWJSmhiicfzyz29D+XfR5157y +ujWNgLzHKoBAVTTOIrpSStEYYdNhRMPTIZM74i29t0GNYHIY7Idmq1ZTaCtq1TMaAaE WmVHAO0cwwR6xIVJSrOu2OEogfXBS/BjedAnKoPUEX2tqR2ndn70Mr5a51WlH6RCwZQq 0oQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738367869; x=1738972669; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=S/RN568Fmuvl8ZzV1YDesmJM5KfuLeOghoyLrEkHA3k=; b=siDBo8/jIeA3Qo2sz6s3qHpUiWVtjp35dbMiWKRi4pnZOzpOfg5OyJDntv5Vu+yiXe HCHJbSzcYTvFZjOeS8mehj6R+NH2gdtKB9ngB5w/9Nexl5bE19OEJpgz8fGTDe/I2Vvr xpSy3zB563LPl66+PSP3JtNr9t5dCtIBGSB2wkLsLJAlTBez9trHkxfvpY0vg8H8KoHZ pxxMdRl7IDw8KPiPYulbXR1mnh0QFxjncTDcaxilgk6BULw+kZVDhbq85UIK7eoeJuI4 88lVq+BuY7BPDEtW7/VUQAr2dOW2n1PxSpO5QNsr5pecuC83SNmPTEv4lMSm1JoK7U0O gjFA== X-Forwarded-Encrypted: i=1; AJvYcCWMJmiAj3mW9hJ7nsOzP+s3aiWitCDMCczPbUAUXqbZsTH472GtxZXJgNTIfY4UBpWcSPgAxw==@lists.bufferbloat.net X-Gm-Message-State: AOJu0YwWGWO+tmv/OoOAMPsgNXOOe2JhDdE7aYUf7VONV0GBv8nbziwd Z/1Xe9lnY5yFrZ+NnxpsluzLcKF+JN7VxPKUIgYv1zuIBj6Dm6/r4DjE2o2sEhxXGl5Mx0VVbCN rOuzQcWPRGSTqGDCW78nP2vXAx4jkIg== X-Gm-Gg: ASbGncsOCDZdmEJbm1BUogX+KCiSDd/o5AH14psuytlq1RhBRvzTZytWPL/4rOThsHZ aMz6W8/slbokq66NMJJEIpLQLax1xAMDrssnE/nkn4IJaR5nXExnV3tAPBD1KrPEpKJVxwJXRbY 6/XP9FSjypIcg+5In4shEmrjgvi0+DwA== X-Google-Smtp-Source: AGHT+IGb9rt6ONkt+qHyGEbdOcLR2zbvcxu7TtEVldsh0Rz7XDcG+Zv1lzJb0Fa8Wi9/EgG09vdqub8QJAO2jEVlzaU= X-Received: by 2002:a05:6871:5e14:b0:29f:af5b:ef49 with SMTP id 586e51a60fabf-2b32f018fbcmr8739792fac.10.1738367869281; Fri, 31 Jan 2025 15:57:49 -0800 (PST) MIME-Version: 1.0 References: <48F77C27-0E57-4F96-9BD8-238CC93342F8@gmail.com> In-Reply-To: From: Dave Taht Date: Fri, 31 Jan 2025 15:57:35 -0800 X-Gm-Features: AWEUYZmcpXwACj0AU-j7ZpxVRtTEFHaV02PhZSKpd40mqp9xlqciLlHvK0kbNh4 Message-ID: To: Sebastian Moeller Cc: Rich Brown , Rich Brown via Bloat Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [Bloat] Comcast & L4S 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: Fri, 31 Jan 2025 23:57:50 -0000 Here are the positives: For the first time, a major ISP has deployed the PIE AQM on all traffic. Before now Comcast was only doing that on the upstream. That=C2=B4s 99.99% of all current comcast traffic getting an AQM on it. WIN= . The L4S side being enabled will also result in some applications actually trying to use it for cloud gaming. There is a partnership with valve, meta, and apple, that implies that we will perhaps see some VR and AR applications trying to use it. I look forward to a killer app. Negatives include explicit marking and potential DOS vectors as often discussed. I do feel that in order to keep up with the jonesies, we will have to add optional l4s marking to CAKE, which should outperform pie (mark-head), I just wish I knew what the right level was - at 100Mbit it seemed at 2ms was best. We also need to remove classic RFC3168 style marking and drop instead when the L4S bit is present - across the entire linux and BSD ecosystem. There was an abortive attempt last year to get dualpi, accecn, and prague into mainstream linux, but it stumbled over GSO handing, and has not been resubmitted. ACCECN seems to be making some progress. This makes it really hard to fool with this stuff. On Fri, Jan 31, 2025 at 5:27=E2=80=AFAM Sebastian Moeller via Bloat wrote: > > Hi Rich, > > > > On 31. Jan 2025, at 14:20, Rich Brown via Bloat wrote: > > > > Google Alerts sent me this: https://www.webpronews.com/comcasts-latency= -leap-a-game-changer-in-network-performance/ > > > > Key quote: "Compatibility and Ecosystem: For L4S to have a significant = impact, it requires an ecosystem where both the network infrastructure and = the end-user devices support the standard..." > > > > Can anyone spell "boil the ocean"? :-) > > > > Or am I missing someting? > > Well, the whole safety mechanisms in L4$ are laughably inadequate... this= "design" essentially exposes a priority scheduler* without meaningful admi= ssion control to the open internet. This is so optimistically naive that it= almost is funny again. I wish all the effort and hard work to make L4$ hap= pen, would have been put in a reasonable design... but at least I learned o= ne of the IETF's failure modes, and that is at least something valuable ;) > > > *) Just because something is not a strict preempting priority scheduler d= oes not make it a good idea to expose it blindly... a conditional priority = scheduler with e.g. L4$' weight share of 10:1 already can do a lot of harm= . > > > > > > > > _______________________________________________ > > Bloat mailing list > > Bloat@lists.bufferbloat.net > > https://lists.bufferbloat.net/listinfo/bloat > > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat --=20 Dave T=C3=A4ht CSO, LibreQos