From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-we0-x22a.google.com (mail-we0-x22a.google.com [IPv6:2a00:1450:400c:c03::22a]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 2518821F1F3 for ; Thu, 20 Mar 2014 09:29:32 -0700 (PDT) Received: by mail-we0-f170.google.com with SMTP id w61so789086wes.29 for ; Thu, 20 Mar 2014 09:29:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=fIlYR1UgrreIyMyBUKOu9LSg/SnxtE6zENnmqeEs7eo=; b=rtBKgPq6k+o9IeltRPD276a3hMLicLzQzlgDy1uuA6ONP60k7iLbq+P25TLo2/UrMY Gs3h6aQpUyZrOc7z1mUp2yBx4xuH8AjaGDeVCFMiy4EmcE6ouE4uK2lguZSLojmNoInm j51tI2+dTCCSK+y/fXq7IBKOEK344+lJkPmqiJASTSgpjS/nvHg3DKDm8uM6iqoyEvEs QL+sn87lhVpoTfIPOyY9wl7AIXqakvmey9hwIXLd2Hw1BVk6q6SlJ571gqA/UG4UbuEu XBl/acoL5Us4lHqNwmPSswHVRFGeYP35wOX5s0fVkAGb9W08eUVLMmwZ88hhQMvRwPFR 0Ggw== MIME-Version: 1.0 X-Received: by 10.195.13.103 with SMTP id ex7mr34627209wjd.3.1395332970023; Thu, 20 Mar 2014 09:29:30 -0700 (PDT) Received: by 10.216.8.1 with HTTP; Thu, 20 Mar 2014 09:29:29 -0700 (PDT) In-Reply-To: <87eh1wc05c.fsf@toke.dk> References: <20140318145221.GA31327@sesse.net> <07BD4518-2A7E-4F43-8978-791E3B2BDA2A@cisco.com> <87eh1wc05c.fsf@toke.dk> Date: Thu, 20 Mar 2014 09:29:29 -0700 Message-ID: From: Dave Taht To: =?ISO-8859-1?Q?Toke_H=F8iland=2DJ=F8rgensen?= Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: bloat Subject: Re: [Bloat] AQM creeping into L2 equipment 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: Thu, 20 Mar 2014 16:29:32 -0000 I find it puzzling that you still lose the measurement flows early on. Sett= ing some QoS on via WTD might be interesting. sub 2ms performance under this load is quite good. If you have a later OS than 3.13 on the sources/sinks you might want to try sch_fq (and sch_pfifo_fast for reference) - the improvements to Linux's TCP are such that on a short path like this that the control loop stays very tight - only two TSO offloads per flow, really accurate use of tcp timestamps, etc. See also if you have hardware flow control enabled (via ethtool) On Thu, Mar 20, 2014 at 9:20 AM, Toke H=F8iland-J=F8rgensen = wrote: > Dave Taht writes: > >> The standard test that I'm most interested in is the 2 ports into 1 topo= logy: >> >> SOURCE >> | >> SWITCH >> | | >> BOX1 BOX2 > > Did a couple of tests of this with the default configuration of a Cisco > WS-C2960X-24TD-L switch. Graphs and data files here: > > http://kau.toke.dk/experiments/cisco-switch/cisco-c2960x.html > > Conclusion: My test boxes need offloads and quite a bit of driver > queueing to drive the 1Gbps link, which makes it difficult to say > anything about the switch... > > Haven't fiddled with the QoS settings, but from what I can see they are > rather limited, and takes a great deal of fiddling to setup (at least > for someone who, like me, has pretty much zero experience with Cisco > gear). > > If someone has suggestions for other switch configurations that would be > worthwhile testing (as well as some help on how to configure it), I'll > be happy to run the tests. > > -Toke --=20 Dave T=E4ht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.= html