From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-12-ewr.dyndns.com (mxout-123-ewr.mailhop.org [216.146.33.123]) by lists.bufferbloat.net (Postfix) with ESMTP id 2D1BD2E015C for ; Sat, 12 Mar 2011 15:03:06 -0800 (PST) Received: from scan-12-ewr.mailhop.org (scan-12-ewr.local [10.0.141.230]) by mail-12-ewr.dyndns.com (Postfix) with ESMTP id 5352B934671 for ; Sat, 12 Mar 2011 23:03:06 +0000 (UTC) X-Spam-Score: -1.0 (-) X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 209.85.215.171 Received: from mail-ey0-f171.google.com (mail-ey0-f171.google.com [209.85.215.171]) by mail-12-ewr.dyndns.com (Postfix) with ESMTP id D8F5B934649 for ; Sat, 12 Mar 2011 23:03:05 +0000 (UTC) Received: by eydd26 with SMTP id d26so1475417eyd.16 for ; Sat, 12 Mar 2011 15:03:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:subject:mime-version:content-type:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to:x-mailer; bh=2vqcPMnfsZTnowgfdrzPeWh88O4x7Sl/3Zx4ACn2gSs=; b=hpn36y5YzgXbCz/v1/GK/MkgyLMxSlIEehl38g/NZU79fPg/SyTRqNzFL//5/T9a1e trrQBqMQ9n7rK2pexykURSHyMOXpSfe+azHz/XY6q7Eo/dcqowR3FurqYfJ5UvmTQb5I +fimJILkzT6YLA1j8CKKzjKjQt5dV0zmp1AfU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; b=ghi01Vux9xm1aVTKawhCAK98aD/ravmXwV7AKCfcfnK8XQgd2KOT52vqQuX/UbIozZ d7Wfxnpwls1YPgWO9yffFCu/6t0FnzzqhEKk4KeiZ1Q3fS4qsL06iVjcOwb7YOXQv43m 5jVmZaCk2Y7dL1/5n/sliFLgzY2ZQUPJVtZUo= Received: by 10.213.96.220 with SMTP id i28mr2172795ebn.123.1299970985084; Sat, 12 Mar 2011 15:03:05 -0800 (PST) Received: from [192.168.239.42] (xdsl-83-150-84-172.nebulazone.fi [83.150.84.172]) by mx.google.com with ESMTPS id b52sm4642776eei.1.2011.03.12.15.03.04 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 12 Mar 2011 15:03:04 -0800 (PST) Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: Jonathan Morton In-Reply-To: <08621605-30D1-4916-82EE-A4219A653ACD@cisco.com> Date: Sun, 13 Mar 2011 01:03:02 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <4A5D7592-685F-45CC-9429-CE7FC1A289B5@gmail.com> References: <16808EAB-2F52-4D32-8A8C-2AE09CD4D103@gmail.com> <08621605-30D1-4916-82EE-A4219A653ACD@cisco.com> To: Fred Baker X-Mailer: Apple Mail (2.1082) Cc: bloat@lists.bufferbloat.net Subject: Re: [Bloat] Measuring latency-under-load consistently X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 12 Mar 2011 23:03:07 -0000 On 13 Mar, 2011, at 12:21 am, Fred Baker wrote: > At the risk of sounding like someone mentioning a product, let me = mention a product. This assumes, of course, that you're using Cisco = equipment. But it allows you to measure delay (how long does it take to = get from here to there), jitter (first derivative of delay/dt), and = packet loss. Ping does most of this, and is available on your actual computer. A = little post-processing of the output gives you jitter, if it doesn't = supply that natively. The point is, the existing tools don't typically measure latency *under = load*. - Jonathan