From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from g6t0184.atlanta.hp.com (g6t0184.atlanta.hp.com [15.193.32.61]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "smtp.hp.com", Issuer "VeriSign Class 3 Secure Server CA - G3" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 9F45A201251 for ; Mon, 21 May 2012 10:24:42 -0700 (PDT) Received: from g5t0029.atlanta.hp.com (g5t0029.atlanta.hp.com [16.228.8.141]) by g6t0184.atlanta.hp.com (Postfix) with ESMTP id 9E21FC31C; Mon, 21 May 2012 17:24:40 +0000 (UTC) Received: from [16.89.64.213] (tardy.cup.hp.com [16.89.64.213]) by g5t0029.atlanta.hp.com (Postfix) with ESMTP id C39102027C; Mon, 21 May 2012 17:24:39 +0000 (UTC) Message-ID: <4FBA7A57.7010709@hp.com> Date: Mon, 21 May 2012 10:24:39 -0700 From: Rick Jones User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Dave Taht , Tobias Diedrich References: <20120520212944.GK22418@yumi.tdiedrich.de> <20120521003115.GO22418@yumi.tdiedrich.de> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: OpenWrt Development List , codel@lists.bufferbloat.net Subject: Re: [Codel] BQL support in Ethernet drivers (and Kathie Nichols and Van Jacobson's new AQM, codel) X-BeenThere: codel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: CoDel AQM discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 May 2012 17:24:42 -0000 On 05/20/2012 08:48 PM, Dave Taht wrote: > Thx for the numbers! > > Could you do a TCP_RR while under load from UDP_STREAM? If you want to generate pretty pictures while doing so, you can probably tweak http://www.netperf.org/svn/netperf2/trunk/doc/examples/bloat.sh rick jones > > On Mon, May 21, 2012 at 1:31 AM, Tobias Diedrich > wrote: >> Tobias Diedrich wrote: >>> Dave Taht wrote: >>>> In looking over the enormous stack of boards and drivers that openwrt >>>> supports, I see that many of the ethernet drivers don't yet support >>>> Linux 3.3's "Byte Queue Limits", which are discussed here: >>>> >>>> http://lwn.net/Articles/454390/ >>>> >>>> It would be good if more did. They improve network performance in the >>>> general case enormously, particularly when a link is not connected at >>>> it's peak wire speed. >>>> >>>> *Adding* support for BQL to an ethernet driver is trivial, here's an >>>> example of how. >>> >>> I tried adding BQL to the ramips ethernet driver, however I found >>> some interesting behaviour while doing >>> "root@OpenWrt:~# netperf -l 120 -t UDP_STREAM -H myserver" >>> >>> It looks like the briding code still needs to implement this as well? >>> >>> netperf UDP_STREAM: >>> iface limit_min inflight tx mbps remote mbps ping ms >>> eth0 0 ~15000 95.71 95.71 ~10ms >>> eth0 1000000 ~300000 177.98 23.28(*) ~30ms >>> br0 0 ~15000 154.88 33.94(*) ~120ms >>> br0 1000000 ~300000 170.92 25.57(*) ~30ms >>> >>> (*) bwm-ng on the server showed ~100mbps incoming... >> [...] >>> Haven't tried codel yet... >> >> Turns out, it works nicely with codel, even with the bridge: >> >> netperf: netperf -l 120 -t UDP_STREAM -H myserver >> fq_codel: tc qdisc add dev eth0 handle 1: root fq_codel target 5ms >> >> iface eth0 qdisc bql inflight tx mbps sys time ping ms >> eth0 pfifo_fast no n/a 182.98(*) 96.43s ~30ms >> eth0 fq_codel no n/a 177.98(*) 96.09s ~30ms >> eth0 pfifo_fast yes ~15000 95.71 42.73s ~10ms >> eth0 fq_codel yes ~15000 95.19 51.52s ~4ms >> br0 pfifo_fast yes ~15000 155.19(*) 94.24s ~120ms >> br0 fq_codel yes ~15000 90.92 65.52s ~4ms >> >> (*) 100mbit link after the switch, ifconfig eth0 shows no drops, >> so I'm assuming they are getting dropped by the switch. >> >> -- >> Tobias PGP: http://8ef7ddba.uguu.de > > >