From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lj1-x22d.google.com (mail-lj1-x22d.google.com [IPv6:2a00:1450:4864:20::22d]) (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 3349C3BA8E for ; Thu, 6 Sep 2018 19:04:01 -0400 (EDT) Received: by mail-lj1-x22d.google.com with SMTP id s12-v6so10746532ljj.0 for ; Thu, 06 Sep 2018 16:04:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=hVe+KUHDN/pXmb+xNRAmLD2RnrVneQdqURUzlm+3ITs=; b=QlQP/4R1dYA0xZ1dYr+kKwMNTiUmhJc1L4gmG+5ez4H22DH4zRLdXW8/++2V0bH/7l j3PUOAtS55md3sLuITJ1+4R4i6Io8mFwwRHupn9JDODEZ54Pt01jM7ms8JBF5qblwdoR MJ/jP8yDKRW1BHbBuE5vaG09trRgWAcN/orTF39oN2MiE7c65EiGhxS9oBluaQV55U1B OEBY6spHC1rcYfjySFYRjdFD/TY9ck1MMUuU6O7iczIcQnLZdzcHcs2Mee+99mg1QyvH yWcm3fEKzwHg6teCBlxPlwp4JU01g8eLuhYFVO9M+GqLqK8ojtx7X6297x6IKV+rwBPp oBxw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=hVe+KUHDN/pXmb+xNRAmLD2RnrVneQdqURUzlm+3ITs=; b=e55KhPSc0RqlxkBjJvEzjxmnQdhN4oJavTamVCNFzJN8gMQ8/yz8psq3PiNhqbjJYy D/WVLgFUAMLyeedDcI4m4SL8oDGNn/Rtg0MY/ZOHl7UG/uTEsI7XUzHBtG7z7EXtIrYl LtGBqJM/YYYLDFwc14AqcNnlPA5IZk2UQBLghGQ+8iEqrj4hTUaE+jyK0ABC5xiyVezt JI6GLfwOLe2Goq25auZ4OrWa+Ou5ga1FLTtxNhLRe0JhtMyoUVVi/9uueOfZ9Ed17V0s sWesLWq89zvN49q/PYatlOH9WUR91T5htfGaWQxclXCV+pvCLwjj1ISJN015df1/q8V8 0Zmg== X-Gm-Message-State: APzg51AdW7+uEEKrCO3WOytJ/nmVtck25ztDsdOGXyFXmUc2Qh21zAik 9pCoRf4jUIJZmkAQO/2Uoxw= X-Google-Smtp-Source: ANB0VdYW4gQ0VGLkEucxbl/RjBQLGbqvh0wSktAbhlXg6aeBUAHFTSZgK5cxzrTCtt7r99vJ0iEaDA== X-Received: by 2002:a2e:2b1b:: with SMTP id q27-v6mr3123556lje.147.1536275040088; Thu, 06 Sep 2018 16:04:00 -0700 (PDT) Received: from jonathartonsmbp.lan (83-245-232-200-nat-p.elisa-mobile.fi. [83.245.232.200]) by smtp.gmail.com with ESMTPSA id y85-v6sm1011169lfi.46.2018.09.06.16.03.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 06 Sep 2018 16:03:59 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) From: Jonathan Morton In-Reply-To: <2CB335A2-E18F-430F-9331-9AD9B3238D84@heistp.net> Date: Fri, 7 Sep 2018 02:03:58 +0300 Cc: Cake List Content-Transfer-Encoding: quoted-printable Message-Id: <1CFBCFB1-AC8B-4172-A4EB-1CE65DE62EF6@gmail.com> References: <2CB335A2-E18F-430F-9331-9AD9B3238D84@heistp.net> To: Pete Heist X-Mailer: Apple Mail (2.3445.9.1) Subject: Re: [Cake] FreeNet backhaul 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: Thu, 06 Sep 2018 23:04:01 -0000 > On 7 Sep, 2018, at 1:37 am, Pete Heist wrote: >=20 > This router is an old ALIX with kernel 2.6.26, but on the other hand = it does have hfsc + esfq (a variant of sfq with host fairness) deployed, = so if it=E2=80=99s actually controlling the queue, one might suspect = that sfq it could control inter-flow latency at least somewhat. ESFQ has two important faults: it doesn't explicitly control the length = of individual queues (only tail-drops when a global limit is reached), = and it suffers from hash collisions at the full "birthday problem" rate. = So some of your measurement traffic is likely colliding with real = traffic and suffering accordingly. That still makes ESFQ far better than a dumb FIFO. - Jonathan Morton