From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] tcp: cubic scaling error Date: Wed, 25 Oct 2006 23:04:25 -0700 (PDT) Message-ID: <20061025.230425.126576070.davem@davemloft.net> References: <20061025105229.3b93aa17@freekitty> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: doug.leith@nuim.ie, netdev@vger.kernel.org Return-path: Received: from dsl027-180-168.sfo1.dsl.speakeasy.net ([216.27.180.168]:24746 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S1423422AbWJZGE3 (ORCPT ); Thu, 26 Oct 2006 02:04:29 -0400 To: shemminger@osdl.org In-Reply-To: <20061025105229.3b93aa17@freekitty> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Stephen Hemminger Date: Wed, 25 Oct 2006 10:52:29 -0700 > Doug Leith observed a discrepancy between the version of CUBIC described > in the papers and the version in 2.6.18. A math error related to scaling > causes Cubic to grow too slowly. > > Patch is from "Sangtae Ha" . I validated that > it does fix the problems. > > See the following to show behavior over 500ms 100 Mbit link. > > Sender (2.6.19-rc3) --- Bridge (2.6.18-rt7) ------- Receiver (2.6.19-rc3) > 1G [netem] 100M > > http://developer.osdl.org/shemminger/tcp/2.6.19-rc3/cubic-orig.png > http://developer.osdl.org/shemminger/tcp/2.6.19-rc3/cubic-fix.png > > Signed-off-by: Stephen Hemminger Applied, thanks a lot Stephen.