From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-il1-x133.google.com (mail-il1-x133.google.com [IPv6:2607:f8b0:4864:20::133]) (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 BFB643B29D; Tue, 19 Oct 2021 10:17:06 -0400 (EDT) Received: by mail-il1-x133.google.com with SMTP id h10so18558116ilq.3; Tue, 19 Oct 2021 07:17:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=SqqWy5Zsd2OzYXj2N8vHoys31o9IAW7TKAXYcjitUw0=; b=S7YOFdSq1R31wFZpPvSJZ7yUKXmXdSNL6BgrZ/JEsN/J/kMaiaYxnxX4Lt2Gmdxwjs BNDlJERYA95qjr6gJGWzUQcWEAIjA341d1H4UchB0hPuSrXuEljRCU81EyjaeeXIQHbE vTXmL1uUqrGaC4QWZb+XHKQrQ7CdOm2uK31tjCSp7f8RHhaHEvTH//T0ezbzlOS8SS3h Y05hFWmif5QmolFzi6u5GbKbAfXa+cnMJ6bGaIJNWrhXgNl6sJ3T8LDtRxSNPehF/9Ks AHfVzwkw9/Os2cGzClLp5vMAMjsPezAYlkcxT4gsa0u/WNohKTBFey9bwSqVb6de+rFA 1wJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=SqqWy5Zsd2OzYXj2N8vHoys31o9IAW7TKAXYcjitUw0=; b=ScwG/qS3usIFO76+IzVWIztAyp8oS9yYkzueO1s+w8wXVimOACvRj7idUmgKORyr3J rIuqSqyEZuA5jKeSg6RjQ/kK+pkbbcF6mlCXbYXjwlbYEQJSknCKB1Gdr6RkSi3yFX2T yEQg5piPbjTa2QSwQVrMbJVONoM5hcaC+RGuxgZgCUctNeRYs6FeKjhO4gSVerrUJFas 4l/L/FobD+Nz8BJ+w0FTPm/bFbmebxeeYBy27cdKR1hJS13PgcS4cYXGa0Gl/dt27qxv wBBn+rLPK+3tkAPdAMBnpSsuV1oZ2cIu5WitA0NUDw6euE+4/ePmBNozo9Nba4gnXoaq 6TCw== X-Gm-Message-State: AOAM5335hNc4htwQr+wXqQX4vTfbffAsV/BE428z69pCArEJR5Cf5bD8 kOx4+YjgrYsFXsAU4zOKeSzA2khHwKabd4LhnJ0= X-Google-Smtp-Source: ABdhPJyTDZuuleLSQNyXA4bdLYoSdm9aGZ9LuquklclnGtbRuptKYmdNNtKN3rkiVWLDjbYM2FwzXI/V3LhzPYsT8Ks= X-Received: by 2002:a05:6e02:1d9b:: with SMTP id h27mr18834191ila.274.1634653025888; Tue, 19 Oct 2021 07:17:05 -0700 (PDT) MIME-Version: 1.0 References: <87sfx31dt5.fsf@toke.dk> <87pms71cmr.fsf@toke.dk> <878ryqjxke.fsf@toke.dk> <87tuhdgt35.fsf@toke.dk> In-Reply-To: From: Dave Taht Date: Tue, 19 Oct 2021 07:16:52 -0700 Message-ID: To: Sebastian Moeller Cc: =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= , Cake List , ECN-Sane Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [Ecn-sane] [Cake] l4s kernel submission 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, 19 Oct 2021 14:17:06 -0000 On Tue, Oct 19, 2021 at 6:34 AM Sebastian Moeller wrote: > > So that still leaves us with GSO introducing CE "spikes" into the network= , that might not necessarily reflect what would happened if the meta-packet= had been segmented before.... I am not sure the proper term for this, the "wavefront" of a GSO'd packet will get scheduled and not marked, and the tail of the wave, were it not GSO'd, might be marked. The next wavefront, assuming it's accumulated a negative deficit, will all be marked. Now what this means for the next "wavefront" I don't really understand, my guess is packets will start to get paced naturally from the sender but might still be arriving in a bunch to the receiver. On the GRO side, I am glad toke has reassured me that at least in linux, GRO checks all the headers. as for what hardware offloads or the device drivers might do, unknown. In our world we've been splitting up gro/gso in self defense so much that we don't know what the rest of the world looks like. sch_fq has a 3000 byte quantum and always releases two packets by default. > I note that rfc3168 probably will not care, since it will signal a CE mar= k for >=3D a full RTT anyway, but HFCCs will care. I have long thought that responding better to multiple rfc3168 marks in an RTT would be a nice addition for a transport to have. But, no, they don't care. > Regards > Sebastian > > > > > On Oct 19, 2021, at 15:30, Dave Taht wrote: > > > > On Tue, Oct 19, 2021 at 4:19 AM Toke H=C3=B8iland-J=C3=B8rgensen wrote: > >> > >> Dave Taht writes: > >> > >>> my more specific question was gro. On gro assembly is the dscp/ecn > >>> header examined? > >> > >> Yes, and only packets with the same value get aggregated: > >> https://elixir.bootlin.com/linux/latest/source/net/ipv6/ip6_offload.c#= L263 > > > > Good to know. Thx. > > > >> -Toke > > > > > > > > -- > > Fixing Starlink's Latencies: https://www.youtube.com/watch?v=3Dc9gLo6Xr= wgw > > > > Dave T=C3=A4ht CEO, TekLibre, LLC > --=20 Fixing Starlink's Latencies: https://www.youtube.com/watch?v=3Dc9gLo6Xrwgw Dave T=C3=A4ht CEO, TekLibre, LLC