From owner-freebsd-net@FreeBSD.ORG Mon Sep 27 13:17:59 2010 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5F8BC1065672 for ; Mon, 27 Sep 2010 13:17:59 +0000 (UTC) (envelope-from andre@freebsd.org) Received: from c00l3r.networx.ch (c00l3r.networx.ch [62.48.2.2]) by mx1.freebsd.org (Postfix) with ESMTP id C2AEF8FC1B for ; Mon, 27 Sep 2010 13:17:58 +0000 (UTC) Received: (qmail 81818 invoked from network); 27 Sep 2010 13:10:30 -0000 Received: from localhost (HELO [127.0.0.1]) ([127.0.0.1]) (envelope-sender ) by c00l3r.networx.ch (qmail-ldap-1.03) with SMTP for ; 27 Sep 2010 13:10:30 -0000 Message-ID: <4CA09987.8020205@freebsd.org> Date: Mon, 27 Sep 2010 15:17:59 +0200 From: Andre Oppermann User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.9) Gecko/20100825 Thunderbird/3.1.3 MIME-Version: 1.0 To: Maxim Dounin References: <20100512124702.GJ2679@rambler-co.ru> <20100713140051.GV99657@mdounin.ru> <4C5BCE48.5070504@freebsd.org> <20100913172453.GG99657@mdounin.ru> <20100927081217.GM44164@mdounin.ru> In-Reply-To: <20100927081217.GM44164@mdounin.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-net@freebsd.org, Igor Sysoev , Lawrence Stewart Subject: Re: net.inet.tcp.slowstart_flightsize in 8-STABLE X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Sep 2010 13:17:59 -0000 On 27.09.2010 10:12, Maxim Dounin wrote: > Hello! > > On Mon, Sep 13, 2010 at 09:24:53PM +0400, Maxim Dounin wrote: > > [...] > >> Andre, could you please take a look at one more patch as well? >> >> Igor reported that it still sees 100ms delays with rfc3465 turned >> on, and it turns out to be similar issue (setting cwnd to 1*MSS) >> for hosts found in hostcache. >> >> The problem with setting cwnd from hostcache was already reported >> here: >> >> http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/92690 >> http://lists.freebsd.org/pipermail/freebsd-net/2007-July/014780.html >> >> As using larger cwnd from hostcache may cause problems on >> congested links (see second thread) I changed code to only use >> cached cwnd as an upper bound for cwnd (instead of fixing current >> code). This is also in-line with what we do on connection >> restarts. >> >> We may later consider re-adding usage of larger cwnd from >> hostcache. But I believe it should be done carefully and >> probably behind sysctl, off by default. > > Ping. Thanks for the reminder. I'll disable priming CWND from hostcache. -- Andre