From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bw0-f43.google.com (mail-bw0-f43.google.com [209.85.214.43]) (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 3B1E1201906 for ; Tue, 11 Oct 2011 06:51:30 -0700 (PDT) Received: by bkas6 with SMTP id s6so14117511bka.16 for ; Tue, 11 Oct 2011 06:51:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=message-id:date:from:organization:user-agent:mime-version:to:cc :subject:references:in-reply-to:content-type; bh=JpNYggvDO6TtB+jDj7TCSBo3Ne4bZRmvQlOCijRKkco=; b=HDCX6UKt+UQPhKRPJMcU5oyHoUcf9DFmMaTucguukVeCSiq/1HthFAiMcb8SHObB2p FR7zleqrvLeNnbMIq4mshUnRCUmmJPlcafFGPZnNeDHfy+5cX1Aj/wKLzusCMDIOfJVx trkUiRxLS7EUrcd5A2Lx2xI95mhJLDTGYNyyA= Received: by 10.204.150.90 with SMTP id x26mr9585285bkv.6.1318341088675; Tue, 11 Oct 2011 06:51:28 -0700 (PDT) Received: from [192.168.0.63] (lincs-gw.enst.fr. [137.194.164.55]) by mx.google.com with ESMTPS id k26sm21287877bks.1.2011.10.11.06.51.27 (version=SSLv3 cipher=OTHER); Tue, 11 Oct 2011 06:51:28 -0700 (PDT) Message-ID: <4E9449DF.4010401@gmail.com> Date: Tue, 11 Oct 2011 15:51:27 +0200 From: =?UTF-8?B?RGF2aWQgVMOkaHQ=?= Organization: Bufferbloat.net User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.23) Gecko/20110922 Thunderbird/3.1.15 MIME-Version: 1.0 To: Eric Dumazet References: <4E941A05.2050705@gmail.com> <20111011115816.GA24956@uio.no> <1318335234.2538.9.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <1318335509.2538.11.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <4E943FF7.5020208@gmail.com> <4E94408A.4030709@gmail.com> <1318340013.2538.30.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> In-Reply-To: <1318340013.2538.30.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Content-Type: multipart/mixed; boundary="------------030503040308070004040004" Cc: bloat@lists.bufferbloat.net Subject: Re: [Bloat] the observed sack oddity 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: Tue, 11 Oct 2011 13:51:32 -0000 This is a multi-part message in MIME format. --------------030503040308070004040004 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 10/11/2011 03:33 PM, Eric Dumazet wrote: > Le mardi 11 octobre 2011 à 15:11 +0200, David Täht a écrit : >> Of course, it would help if I posted a link to the screenshots! >> >> http://www.teklibre.com/~d/sackoddity/ >> >> On 10/11/2011 03:09 PM, David Täht wrote: >>> I have put up screenshots of tcptrace -G and xplot.org's analysis of my >>> most recent capture of an ipv6 connection over freebox (wired) from a >>> debloat-testing kernel here in france (pre 3.1 by a lot) to a 2.6.16 >>> kernel (the aformentioned netsonar box) in redwood city, ca, both >>> running tcp cubic, over ipv6. >>> >>> at first glance, it looked a lot like a classic bufferbloat trace, with >>> complete with periodic collapses and cubic increasing the window. >>> >>> Then I noticed the sacks. >>> >>> I also have a trace taken between the debloat-testing box and a cerowrt >>> box (running linux 3.04), both running westwood, which shows >>> considerably less undesirable behavior, and I will repeat that test with >>> cubic this evening and post additional data tomorrow morning. > > Who is the sender ? The laptop was the netperf initiator, running 3.1.0-rc4-dbt23 #1 SMP PREEMPT. This is basically 3.1-rc4 + the very few debloat-testing patches which are all specific to wifi. I can easily test against 2.6.38, and with a little work, against linux git head, on the laptop. sysctl on the laptop side is: net.ipv4.tcp_ecn=1 net.ipv4.tcp_sack=1 net.ipv4.tcp_dsack=1 net.core.rmem_max = 2097152 net.core.wmem_max = 2097152 net.ipv4.tcp_rmem = 4096 87380 2097152 net.ipv4.tcp_wmem = 4096 65536 2097152 on the netsonar side remotely (2.6.16), it is whatever the defaults are. Updating a server in bloatlab #1 in California is a little harder, as you might imagine, but I should be able to get that done by next week. > Is some WIFI involved ? No. > "netstat -s" on the receiver would help > I will rerun the tests. > This might be a truesize mismatch. > > I saw those patches being discussed but do not understand the implications. -- Dave Täht --------------030503040308070004040004 Content-Type: text/x-vcard; charset=utf-8; name="dave_taht.vcf" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="dave_taht.vcf" YmVnaW46dmNhcmQNCmZuO3F1b3RlZC1wcmludGFibGU6RGF2ZSBUPUMzPUE0aHQNCm47cXVv dGVkLXByaW50YWJsZTpUPUMzPUE0aHQ7RGF2ZQ0KZW1haWw7aW50ZXJuZXQ6ZGF2ZS50YWh0 QGdtYWlsLmNvbQ0KdGVsO2hvbWU6MS0yMzktODI5LTU2MDgNCnRlbDtjZWxsOjA2Mzg2NDUz NzQNCngtbW96aWxsYS1odG1sOkZBTFNFDQp2ZXJzaW9uOjIuMQ0KZW5kOnZjYXJkDQoNCg== --------------030503040308070004040004--