From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.17.20]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 993623B25E; Mon, 16 May 2016 06:34:48 -0400 (EDT) Received: from android-71f81e976a259a8c.lan ([93.237.69.26]) by mail.gmx.com (mrgmx101) with ESMTPSA (Nemesis) id 0Lu3J4-1blnkm10KM-011R9d; Mon, 16 May 2016 12:34:30 +0200 User-Agent: K-9 Mail for Android In-Reply-To: References: <1462205669.5535.254.camel@edumazet-glaptop3.roam.corp.google.com> <1462464776.13075.18.camel@edumazet-glaptop3.roam.corp.google.com> <1462476207.13075.20.camel@edumazet-glaptop3.roam.corp.google.com> <20160506114243.4eb4f95e@redhat.com> <20160506144740.210901f5@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable From: Sebastian Moeller Date: Mon, 16 May 2016 12:34:24 +0200 To: David Lang ,Roman Yeryomin CC: make-wifi-fast@lists.bufferbloat.net, Dave Taht , ath10k , "codel@lists.bufferbloat.net" , "netdev@vger.kernel.org" , OpenWrt Development List Message-ID: <1E11CBFE-1471-4ECC-8D34-9172B61D3F59@gmx.de> X-Provags-ID: V03:K0:xCDa3RBabaXOja9fXbdwH0Ory3eScoRFZ/7teENMwQUW4myiDgj 9IzbnbsWOOtUK0QwRZVQYWaWe8S59A9OwyNPFXTry2/KVfUt/4BvQ4ZbxWRr+kd6bei6cvh pyqJZsa9dtatd+Tap6BXOK5Vz504GNxIQxTSWVbVhkRhvTUfdoGnoymsbPlDDUk9NjLYB2U 8KtD0Yj2F83jETuk/e1bg== X-UI-Out-Filterresults: notjunk:1;V01:K0:sE+sP5Yk/Zc=:2RVQQGRg6MjVl5j7FH8rOH Iu8/mgc7xayzt6Ouh2473p3NeYme7QMaHGxPzGqjS+6gRWNqTf2DxQhZNa5QzWmy0zmUZolVV /T59r5sKbEtTCKinrTTzlWPMJQNg7Rg+DfGC8EC20E1U2F9MtWFj5OpdrA8/+ooRHZd4Uheqx 9AagRckClVb4bgmArW9ohaC7VjkoQKnDb5MYY8b2XSiDJIw2VH49VY2j8lBqEfdvGlhTwg8wl WAbEG/G6c5sjMdGvwBPzN+g+C8Kjmnbpi0/PpH/FGLPo8B3saGNAsyGKs68IjTLTyWDgC1RVV QzYAkR4iey5/tIcX7wWsNsgTAO/T2PKnKAblJMvGBtFjc/w9QD8OBmA2wICwE6p5U4AbDDD29 XGcWUKgtXd/S0qqoZnuyciIsJyqqindyNyTwVDSEoux5P8z2bIeIKVjQmT7EVNDjENPauSTlK OmKWWrxSSyFjXGFxP7Um8aA9NBtk1grV5jxvHpcqz8hSye+vxVvHP0Gx1mDNgo/mPeVvY/2/a A7PZ6Hq1KFxTdWaJ4c30Hro/m5x6N2fwN5C4vljkDbaBgNdTSQ1qKnx5mu1o9pdvacw5qLKco Pv6HdGA+LJv8dL6GaSMVFW5Sb+cF7hVn5f8UPic052MOOvgfwNXom41y31CSAxqdJyh9QYQQt wryhtQP1H8x8zSW3sBgh3Oh9y4i8Q0P7ahAiLWQWzcaJv+vonvzaflBm3bqa8IQM5p14Hz0qa Csanem6jw3dKEt2WKwxz2XjsxNGOTI0+EdunhLGxJS9vMMp3Oqro7xNeLgbmAQ7u3uqu/GCuP 1b5sAN8 Subject: Re: [Codel] [OpenWrt-Devel] [Make-wifi-fast] OpenWRT wrong adjustment of fq_codel defaults (Was: fq_codel_drop vs a udp flood) X-BeenThere: codel@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: CoDel AQM discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 May 2016 10:34:49 -0000 Hi David, On May 16, 2016 10:46:25 AM GMT+02:00, David Lang wrote: >On Mon, 16 May 2016, Roman Yeryomin wrote: > >> On 16 May 2016 at 11:12, David Lang wrote: >>> On Mon, 16 May 2016, Roman Yeryomin wrote: >>> >>>> On 6 May 2016 at 22:43, Dave Taht wrote: >>>>> >>>>> On Fri, May 6, 2016 at 11:56 AM, Roman Yeryomin > >>>>> wrote: >>>>>> >>>>>> On 6 May 2016 at 21:43, Roman Yeryomin >wrote: >>>>>>> >>>>>>> On 6 May 2016 at 15:47, Jesper Dangaard Brouer > >>>>>>> wrote: >>>>>>>> >>>>>>>> >>>> >>>>> That is too low a limit, also, for normal use=2E And: >>>>> for the purpose of this particular UDP test, flows 16 is ok, but >not >>>>> ideal=2E >>>> >>>> >>>> I played with different combinations, it doesn't make any >>>> (significant) difference: 20-30Mbps, not more=2E >>>> What numbers would you propose? >>> >>> >>> How many different flows did you have going at once? I believe that >the >>> reason for higher numbers isn't for throughput, but to allow for >more flows >>> to be isolated from each other=2E If you have too few buckets, >different flows >>> will end up being combined into one bucket so that one will affect >the other >>> more=2E >> >> I'm testing with one flow, I never saw bigger performance with more >> flows (e=2Eg=2E -P8 to iperf3)=2E > >The issue isn't performance, it's isolating a DNS request from a VoIP >flow=20 >from a streaming video flow from a DVD image download=2E > >The question is how many buckets do you need to have to isolate these >in=20 >practice? it depends how many flows you have=2E The default was 1024 >buckets, but=20 >got changed to 128 for low memory devices, and that lower value got >made into=20 >the default, even for devices with lots of memory=2E And I believe that the reduction was suboptimal, we need the Hash buckets = to spread the glows around to avoid shared fate due to shared buckets=2E=2E= =2E So the 1024 glows make a lot of sense even if the number of real concu= rrent flows is lower think birthday paradoxon=2E The change came because at full saturation our reduced packet limit only a= llowed one packet per bucket which is too low for decent performance=2E=2E= =2E also less hash buckets make searching faster=2E Since we now can specify a memory limit in addition to the packet limit, w= e should set the packet limit back to its default of 10240 and instead set = the memory limit to something same for each platform=2E This will effective= ly have the same consequences as setting a packet limit, except it becomes = clearer why performance degrades and I at least take a performance hit glad= ly over a forced oom reboot=2E=2E=2E=2E > >I'm wondering if instead of trying to size this based on device memory, >can it=20 >be resizable on the fly and grow if too many flows/collisions are >detected? > >David Lang >_______________________________________________ >openwrt-devel mailing list >openwrt-devel@lists=2Eopenwrt=2Eorg >https://lists=2Eopenwrt=2Eorg/cgi-bin/mailman/listinfo/openwrt-devel --=20 Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E