From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io1-xd30.google.com (mail-io1-xd30.google.com [IPv6:2607:f8b0:4864:20::d30]) (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 171E03B2A4 for ; Tue, 9 Mar 2021 13:58:37 -0500 (EST) Received: by mail-io1-xd30.google.com with SMTP id k2so15110189ioh.5 for ; Tue, 09 Mar 2021 10:58:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to :content-transfer-encoding; bh=cfF3IENX0YTnDwbjyylGEuKMzdjzZOUDNCXPRJnjGjw=; b=r4bggOzUsGdlJoS/wrs/UK0b0oYsiNJaF1hoDAkaWcWckbgUTGiWidST0VD1PDfJci txDpNnyh+3W2ikaM6X6cBVbve0ygP6PxL6of/JB80BainXMpavTH62k3F4On8TBDO89I vZCfxgu9obB5ob+AWG22/OYvhjhjxtcX9h7csmOiDAdE1XTsA5cLZDFJQvb7+5VCdnHI 4FDD4aMmr5euNSfJOdBVVW/kB3McbJvf1YeZEWiJ3m2DKJkb3MF1pWbTIAEQc0/lhSrR NA8fFOQKiQtmO2TnbbqRxy0bRJaKi09kut+doudIKEjfgRmM4qx3p1LDCTL/aYY1MUKC 5oow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to :content-transfer-encoding; bh=cfF3IENX0YTnDwbjyylGEuKMzdjzZOUDNCXPRJnjGjw=; b=axybmOLj0kmxv9DpcUhpLzoX67GqZmZdy/NA1/kwHXjaSkkQg10S0gI3qcQtcpUzbh x8B47+Ir57gl0LgQcKNCl1yH9F/T3WOeM45tgdP7LHhFYykZX0CJaQsXuPJ4vHI17GhW jINNe2To55/0mrY3f9y9om19WRK7DEqwUVMxD9x8a+PEyt+a5olqoXZeSo5pSRZkXmiM Zi/nI5GVjwe0t4/Qn0x1EfSXPtP7M/Hehd722EUV1km2t22gnocsDK5ii5WA9m2wSlK7 tjzqlGGakt5Ig5ZGi7Ub5IfagIDdmyWfQ12/yG/eYxAlO4kz1m2wtXZ3oj7pJ8V1uE3F MYSw== X-Gm-Message-State: AOAM532Tbyy7OHw1DeVG9y0nVzHmRuSjLbCqB0RcuPnnNWPORY6CQSbr 7d3+6MmwWbsiwl8kfTqwWID0/gCkAfOJ38QeXXwN8YabG6U= X-Google-Smtp-Source: ABdhPJzUYBquqWRiZje22RlHODj4u4/4a3FeQQVZK98UiUv+2tGTdS6ruNWtY39yP6ujuKyiQ1gv+CBcQ9a8nRw3nFI= X-Received: by 2002:a5d:9641:: with SMTP id d1mr23577556ios.123.1615316316247; Tue, 09 Mar 2021 10:58:36 -0800 (PST) MIME-Version: 1.0 From: Dave Taht Date: Tue, 9 Mar 2021 10:58:25 -0800 Message-ID: To: ECN-Sane Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [Ecn-sane] a data point on syn and dscp X-BeenThere: ecn-sane@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussion of explicit congestion notification's impact on the Internet List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Mar 2021 18:58:37 -0000 I have been noticing some syn packets get marked AF21 in transit. I haven't looked into it hard as yet, but it might be a useful statistic to be collecting from various vantage po= ints. secondly, I am under the impression that linux now paces even the initial iw based on the syn/ack pairb, but haven't tracked it very much. Is this true? I haven't built a kernel in ages, nor reviewed git logs. Trying to get on it now. Now, I don't mind if the syn or syn/ack are getting prioritized very much - delay in one direction does not equal the delay in the other, but it does lead to a slight mis-estimate as to how to fill the pipe with that initial burst being prioritized outside the main fifo. (fq_codel of course, essentially offers zero delay and a correct estimate of the length of the pipe for both kinds of packet) this leads to my final question in that early sce and l4s experiments did have a lot of trouble with having to pace the initial burst, and I don't know what is actually done there, now, in current oses. --=20 "For a successful technology, reality must take precedence over public relations, for Mother Nature cannot be fooled" - Richard Feynman dave@taht.net CTO, TekLibre, LLC Tel: 1-831-435-0729