From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.15.15]) (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 626D521F62A for ; Fri, 23 Oct 2015 00:59:06 -0700 (PDT) Received: from u-089-d068.biologie.uni-tuebingen.de ([134.2.89.68]) by mail.gmx.com (mrgmx003) with ESMTPSA (Nemesis) id 0Ltr89-1aY7az3BeX-011DBj; Fri, 23 Oct 2015 09:59:00 +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: <56267AB6.6080604@darbyshire-bryant.me.uk> Date: Fri, 23 Oct 2015 09:58:58 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: References: <9717A3D5-6BF8-4454-A664-AAE4D276C942@gmx.de> <302F7EC4-80C4-42D3-AD9B-E555AD8FE4A5@gmx.de> <56267AB6.6080604@darbyshire-bryant.me.uk> To: Kevin Darbyshire-Bryant X-Mailer: Apple Mail (2.1878.6) X-Provags-ID: V03:K0:B58EqqYSmFqXyCy1yiytgmImhZ5ZsjsNUF0LhqC7KohbdW3eyBl JIRGgpc3Cxu56n266JvrpkNK/Ns7kij95IVxHwW6lrLjlgwjsD7sbHgHVI9UWP2ELBIaVCZ 1tVAte/yO8t0Lhnzyj+hI4Oko/LuTqoHIuFKNph6h/M+CfOpB6Ohya/pOF3b+kU6lGBAwLr bvjbL5pZzKAjKA1TLJ+qw== X-UI-Out-Filterresults: notjunk:1;V01:K0:uwOWz2qFwNQ=:jphXFWgzRmKve7Lilrd8Gu ee4UGNTSvaIVAbH0AemBuXuMKtzs31IIw+B9VI7RtxQJ/jYAZnSr/kaOyDqUBHOnH6JOcWsD5 k2vaLuCk1LJr9XgbFujPrge21Nj9sBrRXWsOfeTjdPFhyL9kuoc1XYrJo20QyMjUod2BB5xOV 1vYhogQ5hrYUDo334yHWDbX5ZOR2AnStslCtm5rUeKeGf43h3Sly2ELtWROGCuO3oCFE+QDWQ SPwXEvesMj94cPlymmF1oyN/Gw7mK/XJhnqQDkSZYqQD0lR69vI1X1z2GWKufcsVD+qDYRYy0 QxWuxOACKL0gISqJbmQrcIGWhtnPq0lHzDz7TlyAgXPZq4j1sdXK7SeK5PJAbwz8p/KTR38yI ZgmfG2mrQ/AmWs5wBivbgXfuQeXWlYfHgSK+ML/H6lpM5JKmhHilbTuGXzIZ74W9dTsLFNhzW AMf+2tNWfK9yxyeqZGTjAfx9VRbM+YTmsjuS/bjMIZ0e6SvstrWf4iFlWARSquJzpoI2MFhtN zZ7J5GGWa3+LNcnkOViltiqY59htS6c1kDqLmbgjuXSAL/pzDouSUcmbGO/L7nCeC3w8Sdwbv G6LfcjO0Cqcl+/e1EPDMZ06mGszssP6BBijkUAF+QWedqdsyAhAiao8/jKnT18Z670JVAot7A l5hGJq001ZFCV8hI1A+Bnz7z3Qf5BrHBUMFvxs3gD8QjRLtJzbcEJbgpPB4QJ56kXrPaJ29lx /NcUWXil9a61o3wfvin/dXQXGS+4CCHnnPV+tIPrmMCD1FV9HTlYCpruLq4pKtCehsllWE0Zh COUuZJF Cc: cake@lists.bufferbloat.net Subject: Re: [Cake] Cake over satellite X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.13 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, 23 Oct 2015 07:59:30 -0000 Hi Kevin, On Oct 20, 2015, at 19:32 , Kevin Darbyshire-Bryant = wrote: > On 19/10/15 20:05, Sebastian Moeller wrote: >> Hi, >>=20 >> On October 19, 2015 10:24:01 AM CDT, Dave Taht = wrote: >>> well, yes, but we can do it in the lab *this week*, before he takes >>> the dingos on.... >> Good idea, als I am at A conference right now and will not find the = time to make the changes to TC in time. I believe that cake should = certainly A) set A reasonable target by default and B) still allow the = user to explicitly request something else. Currently, I believe cake = does only A)... >>=20 >> Besteht Regards >> Sebadtian >>=20 >>=20 >=20 > As an FYI: >=20 >=20 > tc has a number of calculations for interval & target >=20 > If an rtt is specified then target is 5% of interval with 1uS > (microsecond!) and 5mS (millisecond) lower & upper bounds. >=20 > The keyword predefined rtt values are: >=20 > datacentre (100uS), lan (1mS), metro(10mS), regional(30mS), > internet(100mS), oceanic(300mS), satellite(1000mS), = interplanetary(1hour!) > Corresponding targets are 5uS, 50uS, 500uS, 1.5mS and everything from > internet onwards as a 5mS target. >=20 > Although these are the values passed into cake from tc, that isn't the > final story with regard to calculations as cake qdisc has some further > sanity checks. >=20 > If a link bandwidth is specified then the target is set to the max of > '1.5 MTU's worth of link time' and the target value passed by tc. The > interval is set to max of '8 times the calculated target' and interval > value passed by tc. >=20 > So whilst tc supplies an rtt/interval and a 5% calculated target, cake > itself will override this with sensible values if that makes sense for = a > 'slow' link. Thanks for elucidating this. I believe that cake should honor = silly requests by the user as long as those were stated explicitly by = the users and are possible (so target <=3D interval). It is great that = cake has sane defaults and I also believe it would be helpful if cake = noticed the user of unusual parameter configuration, but in the end the = user should be able to control the parameters. (I am fine with having a = =97override_sane_cake_defaults command line switch to make it hard to do = silly things accidentally). =93Do the right thing by default, but allow = unreasonable configurations if asked nicely=94 should be the goal here, = I believe (but I admit Jonathan=92s project, and hence his call) Best Regards Sebastian >=20 > Kevin >=20 > _______________________________________________ > Cake mailing list > Cake@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cake