From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-x234.google.com (mail-oi0-x234.google.com [IPv6:2607:f8b0:4003:c06::234]) (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 EFC573B260 for ; Fri, 6 May 2016 00:57:31 -0400 (EDT) Received: by mail-oi0-x234.google.com with SMTP id x19so127111078oix.2 for ; Thu, 05 May 2016 21:57:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-transfer-encoding; bh=uZaZ6zw1y/ZVH3ihUZ1Q+eldVFkt+aJG40Y/IOgUvhw=; b=Lc638CHUS0YOKCQOiZyc8n8lh4LdkfV446Hg+DJNlo0Ml6W07NU+DUHU4jq+YwI371 Fa3H/NogcVbF5NJSPxw9M0znhbzy4qCrJqIC6XYo0Ehun9xV/TL+uwPV4GUFbMFWSmCw pjOKfyEtYchtHLCPC+jXjXdPuiEG0fJramHbQBfPGxvMF7EROW1rmK+ugSCSJYXkgcoZ 6lNctFdqrhNVWBBoJW9NV554CeSEMhZHS09GwvMj6HRLsxVWRq9WgbvzMDYQOeeep+5a 397pHnzVRjwLWa8Pgk1PBAOwDPxMjH0UqeZuJsoeVoGcRuSbogISgppn7CcNYHVD9/OA CkNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-transfer-encoding; bh=uZaZ6zw1y/ZVH3ihUZ1Q+eldVFkt+aJG40Y/IOgUvhw=; b=cdVlh3D/3j5Z/stioq780QNcaTPaYmYT6qq7P3T3vNZUjht2R1hSNptj4oTva7UVlG JK78FkbHF95RwjqROHlMC8qZLhsOD92DUms6uG8meTbj+RcywO2lza1oqEd0qKRxv1U7 7R5kEqE4dD6Eqz0nE3NGOu7QamRO7TYYvm9MAYsGZO4b9b+pLEZJHs5x9x+MY/Gnd8g6 QpT4IO+cESKtpY4kTqbPk8Zoz7HJPHmHyIFQn9f14Fst7kUAfcFpjRdRpIfFbS3WVLmu kZyfYw5Ghl2s1m59/uUkHJk/KrFLva4XPyaAbKTA2lm84q9D0mvMlYSfoIYv5JwsahEW /Ebg== X-Gm-Message-State: AOPr4FWZKFy1D+eR7LHrL6TqMz3S13s87EWsIsVMB+4mpDS3YoH2xetBqXVsyPxAgngHKlx+3DaDDuii9N8xKQ== MIME-Version: 1.0 X-Received: by 10.202.217.67 with SMTP id q64mr8840853oig.151.1462510651330; Thu, 05 May 2016 21:57:31 -0700 (PDT) Received: by 10.202.81.76 with HTTP; Thu, 5 May 2016 21:57:30 -0700 (PDT) In-Reply-To: <1577AB06-3C14-43D1-92AD-E37CEDCB8E11@gmail.com> References: <1462125592.5535.194.camel@edumazet-glaptop3.roam.corp.google.com> <865DA393-262D-40B6-A9D3-1B978CD5F6C6@gmail.com> <1462128385.5535.200.camel@edumazet-glaptop3.roam.corp.google.com> <1462136140.5535.219.camel@edumazet-glaptop3.roam.corp.google.com> <1462201620.5535.250.camel@edumazet-glaptop3.roam.corp.google.com> <1462205669.5535.254.camel@edumazet-glaptop3.roam.corp.google.com> <2D83E4F6-03DD-4421-AAE0-DD3C6A8AFCE0@gmail.com> <1577AB06-3C14-43D1-92AD-E37CEDCB8E11@gmail.com> Date: Thu, 5 May 2016 21:57:30 -0700 Message-ID: From: Dave Taht To: Jonathan Morton Cc: cake@lists.bufferbloat.net Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Cake] Fwd: [Codel] fq_codel_drop vs a udp flood 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, 06 May 2016 04:57:32 -0000 On Thu, May 5, 2016 at 9:44 PM, Jonathan Morton wro= te: > >> On 6 May, 2016, at 07:35, Dave Taht wrote: >> >> this would be a pretty nifty feature for cake to have in this hostile un= iverse. > > Yes, but difficult to implement since the trailing fragments lose the pro= to/port information, and thus get sorted into a different queue than the le= ading fragment. We would essentially need to implement the same tracking m= echanisms as for actual reassembly. No. At least in the iperf3 case you end up with 3 trailing fragments in their own queue for every first fragment in another queue. Nuking everything once in drop mode with "more fragments" set or a non-zero fragment offset field will do some good. https://en.wikipedia.org/wiki/IPv4#Fragmentation_and_reassembly In the netperf case (which does 64k fragments), even better. And against your typical fragmentation attack, dunno, but all and all it strikes me as a measurable win. > > - Jonathan Morton > --=20 Dave T=C3=A4ht Let's go make home routers and wifi faster! With better software! http://blog.cerowrt.org