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 89C2721F0AE for ; Fri, 23 Nov 2012 08:43:28 -0800 (PST) Received: by mail-ia0-f171.google.com with SMTP id b35so5121571iac.16 for ; Fri, 23 Nov 2012 08:43:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=8tk9lt2p9AJSu1tyTLH9ZBPgMIzdO4h+EYTHaFK7egQ=; b=nx39NZ6jn1xbRQlDW/4vLThYPiFi/+c7lUiKSNu83hfMfonXnR06gS+i5HVzp63aW4 Wu3yy9UuPupuYFMXkAIiHbZf3F/tP6w6tsjLUm1KTuXhA5VA35FkjH6Bu67VgbHtEF1q ZGvCoAudH0ExVwJi5g8+86MGXxC46+2pldXmeL5Iuzrx5Pyw3h4LXVCBtQa6JaaNgvrW o53K9pi8e6lyWRa39xFJWPZU0Ed2kGH+lbOWCyWPL5Hs6b2gzoTr5oMM5cF3YUqXBoUX 1MJv7WR9iEamXWueVPAoTC8TAjh9cM7axPfiOiHTXcLYo+KkvV2nnsayz1ur+MpQaVh1 3/2w== MIME-Version: 1.0 Received: by 10.50.150.144 with SMTP id ui16mr4053472igb.68.1353689004947; Fri, 23 Nov 2012 08:43:24 -0800 (PST) Received: by 10.64.135.39 with HTTP; Fri, 23 Nov 2012 08:43:24 -0800 (PST) Date: Fri, 23 Nov 2012 17:43:24 +0100 Message-ID: From: Dave Taht To: cerowrt-devel@lists.bufferbloat.net, Oliver Neukum Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: [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: Fri, 23 Nov 2012 16:43:41 -0000 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 compl= ete 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) 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. It does indeed bloat up under load, but not badly. 64 bytes from 172.21.42.14: seq=3D49 ttl=3D64 time=3D0.625 ms 64 bytes from 172.21.42.14: seq=3D0 ttl=3D64 time=3D4.184 ms 64 bytes from 172.21.42.14: seq=3D1 ttl=3D64 time=3D3.421 ms 64 bytes from 172.21.42.14: seq=3D2 ttl=3D64 time=3D5.707 ms 64 bytes from 172.21.42.14: seq=3D3 ttl=3D64 time=3D2.843 ms 64 bytes from 172.21.42.14: seq=3D4 ttl=3D64 time=3D6.142 ms 64 bytes from 172.21.42.14: seq=3D5 ttl=3D64 time=3D6.026 ms 64 bytes from 172.21.42.14: seq=3D6 ttl=3D64 time=3D2.373 ms 64 bytes from 172.21.42.14: seq=3D7 ttl=3D64 time=3D13.746 ms 64 bytes from 172.21.42.14: seq=3D8 ttl=3D64 time=3D3.296 ms 64 bytes from 172.21.42.14: seq=3D9 ttl=3D64 time=3D0.699 ms 64 bytes from 172.21.42.14: seq=3D10 ttl=3D64 time=3D2.948 ms 64 bytes from 172.21.42.14: seq=3D11 ttl=3D64 time=3D12.975 ms 64 bytes from 172.21.42.14: seq=3D12 ttl=3D64 time=3D4.238 ms --=20 Dave T=E4ht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.= html