From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.15.19]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mout.gmx.net", Issuer "TeleSec ServerPass DE-1" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 17DF121F261 for ; Sat, 13 Sep 2014 12:48:34 -0700 (PDT) Received: from hms-beagle.home.lan ([93.194.226.142]) by mail.gmx.com (mrgmx001) with ESMTPSA (Nemesis) id 0LjrDd-1Y4Pqg1pNp-00bpQG; Sat, 13 Sep 2014 21:48:31 +0200 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Sebastian Moeller In-Reply-To: <20140913194126.5B0D1406062@ip-64-139-1-69.sjc.megapath.net> Date: Sat, 13 Sep 2014 21:48:31 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <20418644-AB62-43AE-A09E-5F85ED42DBF4@gmx.de> References: <20140913194126.5B0D1406062@ip-64-139-1-69.sjc.megapath.net> To: Hal Murray X-Mailer: Apple Mail (2.1878.6) X-Provags-ID: V03:K0:hia8Uh4PGjkIN5dbtmNxkcFAxOcM38z/MfcfrO4W5ehYxV6/gug cI+bfWyVc9kSqqqQlxyJvdFkvr1HyZxFVtetO/LWHUPScR3yBjyJKcczcIFEA9HaVGIt6YE oc+0NsdngKaLNUsDdHDg1nUp5EkCHJF0C/uOXALfXO136ibQlfLNxSLORwVB8R7lvjELkH3 L39fd+IAZZ/11GAY/GHJQ== X-UI-Out-Filterresults: notjunk:1; Cc: bloat@lists.bufferbloat.net Subject: Re: [Bloat] Measuring Latency 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, 13 Sep 2014 19:49:03 -0000 Hi Hal, On Sep 13, 2014, at 21:41 , Hal Murray wrote: >=20 >> When reading it, it strikes me, that you don't directly tell them = what to >> do; e.g. add a latency test during upload and download. ... >=20 > Does round trip latency have enough info, or do you need to know how = much is=20 > contributed by each direction? RTT is fine, uni-directional transfer time would be too good to = be true ;). The =93trick=94 is to measure RTT without load and under = hope-fully link saturating load and look at the difference in average = RTT and the RTT distributions (so 3 numbers, 2% quantile, average, and = 98% quantlie). I think it really is that simple... >=20 > If I gave you a large collection of latency data from a test run, how = do you=20 > reduce it to something simple that a marketer could compare with the = results=20 > from another test run? I believe the added latency under load would be a marketable = number, but we had a discussion in the past where it was argued that = marketing wants a number which increases with goodness, so larger =3D = better, something the raw difference is not going to deliver=85. Best Regards Sebastian >=20 >=20 > --=20 > These are my opinions. I hate spam. >=20 >=20 >=20 > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat