From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ia0-f171.google.com (mail-ia0-f171.google.com [209.85.210.171]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 1085221F17B for ; Mon, 26 Nov 2012 07:29:37 -0800 (PST) Received: by mail-ia0-f171.google.com with SMTP id b35so7036126iac.16 for ; Mon, 26 Nov 2012 07:29:36 -0800 (PST) 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=nX7CUyKw5ux3S9fO6kvcTLWtJN31L4kcXu0os7zKo9o=; b=ugVn7eIA/fkbIYEWHv6DMa+kRoXRUoLhbdwxRLixHtVVAZ/R7Y4RPMBrBhyP0CIYHO ooVqMLfE9EN9VgF4SVfnNBAV5+xOlBwbC8L96xT30YXGBSrAkNvZXsHYxtJ0jUeSktDo k7rtLDKnxpl8c9gyEoH5p+1QS+cZ8Y4eUT89EpzaPBUDSXZK44NXbyx59buhQujbjh4W EiS31yq8lTd1uy60DGKFDYr4C10+8CeVLz+oIbNKLMY8XfAsog+UfeTjkD2/pYACx5Dk 5UhJ5qcLAntjk6/CcmmHPsOeh3aq0DzPTyv5MyQ6WmmQtB8AddfwSv8VeUYOP6reYuJD tY6Q== MIME-Version: 1.0 Received: by 10.50.161.232 with SMTP id xv8mr12009669igb.22.1353943776506; Mon, 26 Nov 2012 07:29:36 -0800 (PST) Received: by 10.64.135.39 with HTTP; Mon, 26 Nov 2012 07:29:36 -0800 (PST) In-Reply-To: <6215800.d6FWbLqba3@linux-lqwf.site> References: <6215800.d6FWbLqba3@linux-lqwf.site> Date: Mon, 26 Nov 2012 16:29:36 +0100 Message-ID: From: Dave Taht To: Oliver Neukum Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: cerowrt-devel@lists.bufferbloat.net Subject: Re: [Cerowrt-devel] debloating the Pi, maybe not. X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 Nov 2012 15:29:37 -0000 On Mon, Nov 26, 2012 at 4:10 PM, Oliver Neukum wrote: > On Friday 23 November 2012 17:43:24 Dave Taht wrote: >> I was donated a raspberry pi in cambridge and got it booted today. >> It's a very cool >> box, an arm6, running debian, with hard floating point, and getting a co= mplete >> development environment running, getting it to do mesh networking, >> graphics, apache, etc, on a 16GB SD card, was a breeze. >> >> But as for network performance: >> >> It only comes up at 100Mbit, and as noted elsewhere the ethernet chip >> is hooked up over USB. >> >> dmesg >> >> [3.078644] smsc95xx 1-1.1:1.0: eth0: register 'smsc95xx' at >> usb-bcm2708_usb-1.1, smsc95xx USB 2.0 Ethernet, b8:27:eb:18:fc:ac >> >> The best the 3.2 kernel based networking can do is about 75Mbit/sec. >> This eats 68% of cpu in the "system" (sy in top) and 30% in si (system >> interrupt) > > Wow. What did you do to saturate the system like this? Blow empty > UDP packages into the net? A single TCP stream. I built netperf 2.6 with --enable-demo, ran netserver on it, and hit it with single netperf -l60 -H pi I don't remember if the performance I got from it was with -t TCP_STREAM or -t TCP_MAERTS (probably the latter). I will re-run the test with iperf, also, the next time I boot it. Other than this it's a pretty darn cool board, and if I had time I'd dream up a zillion projects for it... It does look rather easy to compile or cross compile kernels for it, too... > >> I had had some hope of this being a good box to put some test tools on, >> but with performance like this, I am back to leveraging the mips stuff. >> >> That said, I do intend to poke at the driver and update to 3.6 when >> I get a chance, since we have patches lying around for both this >> chip and the usbnet code. > > Nothing for performance in the mean time. Note that we don't try to > do interrupt mitigation in usbnet. ok. > Regards > Oliver > --=20 Dave T=E4ht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.= html