From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-x244.google.com (mail-lf0-x244.google.com [IPv6:2a00:1450:4010:c07::244]) (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 CFEC33B260; Fri, 20 May 2016 12:35:22 -0400 (EDT) Received: by mail-lf0-x244.google.com with SMTP id 78so4278128lfq.0; Fri, 20 May 2016 09:35:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=1SCBNKfJnZQBX66wkAFjr/jsrjerYbOxfiCxpsPTS3w=; b=UI8IYMssBAHZUiJqUcz8LzIkqNs0yCCQ+gqK3grSNL9hRBzPLmm3w+RdidAjhFsM5l a/cLEwLENAEZ9fRT15y45QOywEXTj8pktN2Tr4b1YJJz29w5+9/U4Kz+gjeszjLnmiN2 QdSslqKDfiYicZHJNcNJToLEMsP8dTM62GGXsTVv/E24O0gJa5WfVSw10YEyJe2PbaD2 y17+pF304Jvz6QaN4X1B6NBAQgjF01WYVWyCh7BsN2V3VWMV/DPQZ9toyN3kqXBu40l4 HIimxkqTFNfBP6Wy2Xqns4bQvgcYt4ejpUTL3cSymUyFYvmhAy1MpCwfpg11cWcYv+xA pFrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=1SCBNKfJnZQBX66wkAFjr/jsrjerYbOxfiCxpsPTS3w=; b=Q0R9L4wdmucxtONC2fZGMWrkLSLnZBNp2OB7+3ZaweWqk67Vq8tMtL1BtwTpmPcy+D zHl6G0uYTgElVvJJzVSFEXY+CQ8Ft5sKWcon8180O1fWxnh+axtxUvLurZKHc8jEsn9j chAFiS2A6rB/u0Zh16btFb071GqT11JU/xCGm9sI+TdgqARb9MBgRdTqeK7Nk7+y1fJ/ UMF5u+XxUB2h2+NuiZ356JysEVb3y830fR7KuNyXPVU53wONVufclYH41L4OXcZzGHd5 Rp0r/EzgqpTmLMhZ+mT2Int85dOyvSqPJHzU/TjuIlwsNFBO2tBDqXeGkW8MOuXP44/9 Mv5w== X-Gm-Message-State: AOPr4FW09SCirWiM8zP4iO7FcyWzKugJMcj3aRp+ER+TQnjBzwh0ELYVUpnexIDgS43plQ== X-Received: by 10.25.170.140 with SMTP id t134mr1475245lfe.17.1463762121562; Fri, 20 May 2016 09:35:21 -0700 (PDT) Received: from bass.home.chromatix.fi (188-67-138-144.bb.dnainternet.fi. [188.67.138.144]) by smtp.gmail.com with ESMTPSA id z8sm3500304lbv.42.2016.05.20.09.35.20 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 20 May 2016 09:35:20 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) From: Jonathan Morton In-Reply-To: <573F394B.5060009@hpe.com> Date: Fri, 20 May 2016 19:35:18 +0300 Cc: David Lang , cake@lists.bufferbloat.net, codel@lists.bufferbloat.net Content-Transfer-Encoding: quoted-printable Message-Id: <26FFB878-5E6B-47B8-8DFD-A8765421655F@gmail.com> References: <22371476-B45C-4E81-93C0-D39A67639EA0@gmx.de> <991C8B50-192E-431A-819F-F1C5954FF64F@gmx.de> <4C5D0005-2CAA-4C90-BF0D-7177874872AC@gmail.com> <573F394B.5060009@hpe.com> To: Rick Jones X-Mailer: Apple Mail (2.3124) Subject: Re: [Cake] [Codel] Proposing COBALT X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 May 2016 16:35:23 -0000 > On 20 May, 2016, at 19:20, Rick Jones wrote: >=20 > On 05/20/2016 08:12 AM, Jonathan Morton wrote: >>=20 >>> On 20 May, 2016, at 17:04, David Lang wrote: >>>=20 >>> Is it possible to get speed testing software to detect that it's = receiving fragments and warn about that? >>=20 >> Do iperf3=E2=80=99s maintainers accept patches? >=20 > Netperf's maintainer has been known to accept patches so long as they = aren't too hairy. That said, it isn't clear how something operating = above the socket interface is going to know that the traffic it was = receiving was in the form of reassembled IP datagram fragments. >=20 > happy benchmarking, >=20 > rick jones >=20 > I suppose if said software were to dive below the socket interface it = could find-out, though that will tend to lack portability. I=E2=80=99m a little fuzzy on UDP socket semantics. Could the sender set DF on a small proportion of the packets, and listen = for ICMP errors to the effect? These packets could also be salted with = distinguishable data so that the receiver can tell whether the DF = packets, in particular, got through. - Jonathan Morton